INTO BOSNIA'S KILLING FIELDS

ON a cold gray Tuesday in late October, David Rohde reached the limit of his endurance. Since his capture by Bosnian Serb police three days earlier, The Christian Science Monitor reporter had been herded at gunpoint, threatened with death, and forced to stand through the night while a guard toyed ominously with handcuffs. After 48 hours of questioning with virtually no sleep, he had been given one hour to admit he was a spy. Otherwise, the police said vaguely, ''He will come for you.''

''He'' was a man Rohde had last seen playing with a knife, who asked the interrogator when Rohde was going to be sent to a prisoner-of-war camp.

''I just flipped out,'' Rohde remembers. Left with a guard who seemed sympathetic, he began sobbing, disoriented with fear.

''I don't care,'' Rohde told the guard in broken Serbian. ''I'll say anything. If I just keep saying I'm not a spy, they're going to shoot me.''

The guard leaned over a battered desk that was the only real furniture in the tiny interrogation room.''I know you're a journalist. Don't say you're a spy,'' he whispered. ''They won't free you. You'll have a big, big problem.''

With that hurried advice from a man who was supposed to be his jailer, Rohde was pulled back from the brink, and perhaps from a bullet. ''That guy saved my life,'' says Rohde, now safely back in America. ''No doubt in my mind.''

Journalists aren't supposed to become part of the news they cover. David Rohde did, through no choice of his own. When he drove out of Sarajevo in a rented red Citroen on Oct. 29, he was in search of one of the biggest stories yet to come out of the brutal Bosnian war: evidence that rebel Bosnian Serb soldiers had carried out the worst massacre in Europe since the Holocaust. He found such evidence - and also a sharp-eyed security officer with a rifle and a dog.

Rohde was held in an isolated police station for five days, then dispatched to prison like a thief. Threatened with espionage charges and possible execution, he was released only after blunt threats from high US officials and a massive international pressure campaign.

His full story, related in a four-hour monologue, is one of ambition and moral choice, comedy and danger, paranoia and obsession. Most of all it is about the agony of a war that has raged for years and killed thousands of people, yet for many in the West remains dimly seen lightning in the distance.

Some of Rohde's captors treated him cruelly. Many did not - and seemed themselves ordinary men imprisoned in a war of others' making. ''It sounds ridiculous and trite,'' Rohde says, ''but I think that if you can get rid of the extremists and stabilize the situation for a while, these people can live together in peace.''

Danger and opportunity

In person David Rohde does not look like a war crimes correspondent. Quiet, intense, and usually clad in khakis, he instead resembles an apprentice architect or a college instructor on the verge of tenure. He came to the Monitor in 1994, after stints at ABC News and the Philadelphia Inquirer, and impressed superiors with his seriousness and dedication. In October 1994, he was offered a plum post - coverage of the corner of Europe that used to be Yugoslavia.

To reporters, the Balkans conflict is this generation's Vietnam. That means it is an assignment of great danger and correspondingly great opportunity. Years of tragic war have produced human stories that grip the heart: a Sarajevo cellist playing on a street corner, defying snipers to stop his Bach; a hollow-eyed Bosnian Serb guerrilla recounting techniques for slitting throats; children playing in the rubble of what was once the Yugoslav national library. The fighting has also exacted a journalistic toll. More than 40 news professionals have died covering fighting in the Balkans.

Pressure and proximity have made the international press corps in the Balkans close-knit, yet competitive. When Rohde entered this world he did not stay unknown for long.

In the late summer of 1995 he landed a valuable prize: a pass into Bosnian Serb-held territory. The Bosnian Serbs, self-styled rulers of the ''Republic of Srpska,'' are often accused by the West of being the main villains in Bosnia's dismemberment; they have returned this charge with a sullen suspicion that can bloom into paranoia about Western plots. They admit few US reporters, and tightly control where reporters go and whom they interview. Rohde may have received his pass simply because he had not yet had the opportunity to annoy them.

Traveling through Srpska in August, the Monitor reporter searched for, and found, a field that US intelligence had identified as a mass grave of murder victims, Muslim refugees killed after their enclave of Srebrenica was overrun by Bosnian Serb attacks. In a detailed report last August, Rohde wrote of the sad personal papers from Srebrenica he discovered, and a human leg protruding from the earth. The scoop created an international sensation. For Rohde it was also an act that begged follow-up. He was at the forefront of the story of Srebrenica's fate, and that was where he intended to stay.

But ambition is only half the reason David Rohde searched again for killing fields. Guilt, and a sense of moral necessity, made up the other half. In September, he traveled to the town of Tuzla in northeastern Bosnia to interview Muslim refugees who had escaped the Srebrenica area. Many asked him if he knew anything about the fate of their uncles, brothers, husbands, or sons. He couldn't answer most of them and haltingly told them news he had heard of executions of their relatives. The West's interest in Srebrenica atrocities seemed to be declining - and at the same time Rohde knew there were further possible mass graves to be explored.

''I couldn't go face these people who had survived Srebrenica and know that I knew there were four more massacres out there, and that I knew how to get to them,'' Rohde says.

He knew how to reach them because US-based intelligence officials had told him the precise locations of four new graves. Rohde had in his possession a map of eastern Bosnia and had marked the exact locations of the four other mass graves. On the evening of Wednesday, Oct. 25, he sat at a dinner with his fellow reporters in Zagreb, Croatia, gradually withdrawing from conversation. A plan was forming. He felt he had to go. ''I felt sick to my stomach,'' he now admits.

The first thing he needed was accreditation to pass from the government-held Bosnian capital of Sarajevo into territory controlled by rebel Bosnian Serbs. Bosnian Serb press officials, based in the nearby town of Pale, were not about to give him one, so he resorted to forgery. He took an old accreditation - a piece of cardboard that resembled a library card more than a passport - and simply drew over the relevant dates. On Friday, Oct. 27, he traveled to Austria and rented a car. (The rental contract specifically warned against travel to Bosnia.) He bought extra jerrycans for gas and film for his camera. By Saturday, Rohde was in Sarajevo.

Things go wrong

On Saturday night, Rohde talked by phone with Faye Bowers, his Monitor editor in Boston, and told her that he wasn't going to file a story on the Dayton peace talks until Monday. He didn't tell her that he was in Sarajevo, and that he was going back to the Srebrenica area. Rohde told his editor that he had sent an electronic message to her at work explaining what he was up to. ''I wasn't comfortable lying to Faye,'' he says. ''But I didn't want her to feel any responsibility for the trip.''

For a few hours, he briefly considered taking a friend who writes for The New York Times. He decided against it -if the Times got the story, no one would notice his, even if it ran a day or so earlier. And it wasn't fair to have his friend make the dangerous trip with the condition that he hold his story until after Rohde's ran.

So on Sunday morning, Oct. 29, a very nervous David Rohde drove his rented red Citroen to the Sarajevo airport, passed a UN checkpoint, and reached the checkpoint entrance to Bosnian Serb territory. Rohde said he was headed for the press center in Pale.

''The [checkpoint guard] goes, 'Great, let me come with you,' '' remembers Rohde, ''Which is the first thing that goes wrong.''

Rohde insisted he knew where he was going. The guard opened the passenger door. He said again, louder, that he needed no direction. The guard said ''OK,'' shut the door, and waved the Monitor reporter through to Serb territory.

For a while, events then proceeded according to plan. ''I drive through Pale. I'm sweating like a pig. Then I'm relaxing, I'm getting more confident. Things are going well,'' Rohde says.

An hour out of Pale another checkpoint loomed on the road ahead. It was a bad sign. There weren't supposed to be so many checkpoints. Road control inside Bosnian Serb territory was supposed to be loose because of the new cease-fire - or so the Western press corps had believed. Once again Rohde proffered his falsified credential.

''And the cop says something to me, and then I figured out from his Serbian that he was asking, 'Can you give these guys a ride?'''

It was unavoidable - the reporter on a clandestine mission had to take a hitchhiking soldier. This was a problem. Rohde had a camera and film, which, if accidentally discovered, might attract more than mere idle comment.

But the ride proceeded apace, with Rohde's passenger believing the reporter's story that he was just in transit to Belgrade, the capital of Serbia. The pair passed time chatting about the prospects for peace, and the soldier debarked at a checkpoint in Nova Kasaba.

This was, ironically, the site of the one killing field Rohde had already visited. ''I drive by, and I see the old graves, and they're pretty grown over,'' says Rohde. ''I thought about stopping. But then I decided, 'Don't be stupid - new sites are what matters.' ''

A sign that says 'war zone'

At that point, Rohde remembers, he went to plan ''B.'' There were too many checkpoints around, too many policemen. He'd hoped to visit all four new graves in a day, and then proceed over the Drina River into Serbia and relative safety. Clearly, that was not going to be possible. He decided to visit only two alleged massacre sites that were near the town of Karakaj. These sites were far from any line of retreat that Bosnian Muslim soldiers would have taken as they fought their way out of Srebrenica. That meant that any mass graves in the area would likely be filled with the bodies of civilians - not battle casualties as the Serbs said. And Rohde had five detailed eyewitness accounts from refugees who claimed to have survived a Karakaj massacre.

Just south of Karakaj, Rohde remembers, he reached down and loaded his camera. At first, he turned down the wrong road. He pulled up to a sign that said ''War Zone'' and turned around; if he ran into a patrol of soldiers now he was likely to be shot. Then he found the right road. On the left were railroad tracks, just as refugees described. He turned left onto a dirt road and parked behind a railroad overpass to hide the car. He looked to his left, and there it was: a huge area of fresh digging, with heavy truck tracks all around. All was just as his refugee accounts said it should be.

''It's just this surreal sense,'' he recalls. ''Everything is exactly where it's supposed to be. And it's next to a cornfield and next to a hill, and it's quiet and peaceful, and it's a beautiful day with farmers working in the fields nearby.''

Rohde remembers that he went into a sort of shock. He took out his camera and snapped away, aware that he could be arrested at any moment. He took pictures of shoes and canes, and piles of clothing. He found berets, an identity card from Srebrenica, and personal photos with Muslim names on them. He found no bodies or bones, but one of the graves reeked of rotting flesh. He searched for hours. ''I'm there way too long,'' Rohde says.

By then it was around 3 in the afternoon. After taking more shots of a nearby school where refugees said they had been held, Rohde thought that perhaps he should leave. A young boy had stood in the middle of the road, staring at his license plate. He could be across the Drina in minutes. But he decided on a quick visit to the next Karakaj site, near a dam about 20 minutes away. It was crucial that the breadth of the killing - as many as 3,000 people executed - be proved.

'Get away from the car'

Rohde missed the first turn for the dam, too. He turned around and went on, safe in the knowledge that off the main roads there were no police checkpoints, and found the dam easily enough. He parked in a large graveled area. He walked around the area, then up a bluff to a dam. Nothing. He saw an old man walking his dog, who waved. Rohde waved back. At that point, he was discouraged. He got in the Citroen and drove to a second graveled area. He parked, looked to his left, and there they were: two human femurs. Rohde quickly loaded his camera, relieved to be done. This was all he would need. He opened the door. ''And I step out of the car, and the old man yells. I look out, and he's standing there with the dog and a big rifle. And he says, 'Get away from the car! Put your hands up!' ''

Rohde would soon be in the hands of Bosnian Serb security. It was Sunday, Oct. 29, about 5 or 6 in the afternoon. ''I spent many hours in my cell wondering if these two femurs were worth it,'' he says.

Faye Bowers, the Monitor editor who handles Bosnia stories, arrived at her desk in the Boston newsroom on Sunday at 6:30 a.m. She checked her electronic mail and found a message from David Rohde telling her the truth about where he had gone and what he was looking for. She was worried immediately. Rohde's first grave-site excursion had been dangerous, and this one seemed much more so - he had gone in alone, and the Bosnian Serbs had been furious at his first grave story. The paper's higher-ups weren't going to be happy.

* First in a three-part series. Monday, five days of interrogation.