FROM the United Nations-controlled airport outside town, the flag appears as a white dot near the base of the massif whose blue-grey bulk dominates the southwestern horizon of Sarajevo.
As long as that flag flies, the 360,000 people trapped in the Bosnian capital know that the Muslim-dominated Bosnian Army controls Mt. Igman.
Since the end of June, Bosnian Serb forces have sought to conquer Igman, the last territory adjacent to Sarajevo that remains in Bosnian Army hands.
Mt. Igman has been the lone route by which Bosnian troops and supplies have been able to pass into and out of Sarajevo. It provides the only passage from the capital to the encircled eastern Muslim-dominated enclave of Gorazde and Bosnian Army-held towns in the center of the war-ravaged former Yugoslav republic.
From the massive heights, Bosnian troops have also supported compatriots in the outlying Sarajevo suburbs of Sokolovic Colony, Hrasnica, and Butmir, which sit between the foot of the mountain and the airport.
The loss of Mt. Igman would constitute perhaps the greatest military and psychological defeat suffered by the Bosnian Army in the brutal conflict. Many worry it would quickly lead to the fall of Sarajevo itself.
"It will be a major new challenge to take care of [Sarajevans] with winter only four months away," says Peter Kessler, spokesman for the United Nations High Commissioner on Refugees, speculating on the cost of Igman's fall.
"We can say that this is the beginning of the end of the Muslim forces in the area and the capture of the city of Sarajevo," asserted Spasoje Cojic, a Bosnian Serb commander involved in the offensive against Mt. Igman. "As for capturing Igman, this is a strategic matter. The war started in Sarajevo, and it is going to finish in Sarajevo," Mr. Cojic told a Western television crew last week.
Col. Stjepan Siber, a Croatian member of the Sarajevo-based Bosnian Army high command, denied in a Monitor interview that the fall of Mt. Igman would open Sarajevo to conquest. But he acknowledged that the capture of the mountain "would be a great catastrophe and a lot of people would die."
Unlike the morale-boosting propaganda pumped out by the Sarajevo news media, Colonel Siber declined to exclude the possibility of such a calamity. The supply of munitions, once trucked through Bosnian Croat territory, has been cut off, he said.
He said that the Bosnian Army, which has been fortifying Mt. Igman since the war began, had obtained munitions from its erstwhile Bosnian Croat allies in central Bosnia. But that cooperation ended when the Croatian Defense Force, an ultranationalist militia known by the initials of HVO and directed by Zagreb, turned on the Bosnian Army in March.
As a result, the Bosnian Army is facing a dramatic shortage of ammunition for one of the largest concentrations of the very limited heavy-caliber artillery it possesses. "We are well prepared on Igman in a technical sense," Siber says. "But if we don't have ammunition, if we don't have anti-tank weapons, could we stop the aggressors with only our bodies?"
Haris Abdurahmanovic, a Bosnian soldier from Sarajevo, says that because of the ammunition shortage, Bosnian troops must get close to Bosnian Serb tanks and armored personnel carriers to make sure they do not waste their shots. "There are a lot of dead and wounded," Mr. Abdurahmanovic says.
The Bosnian Serb offensive began late last month with about 10 days of heavy shelling on the outermost Bosnian Army lines in Trnovo, located about 15 miles to the southeast of the mountain.
On July 10, a Bosnian Serb ground attack caught the Bosnian Army unawares, triggering a massive flight by soldiers and almost 7,000 Muslim civilians back to Mt. Igman, according to Tomislav Chetouaae, a French aid worker who was on the scene.
"The [Bosnian Serbs] pushed very hard. The Army was caught unprepared. It just retreated," Abdurahmanovic says. Bosnian Serb infantry and armor drove virtually unimpeded toward the mountain. The forces were checked on July 23 by a concerted Bosnian Army counterattack, Abdurahmanovic says.
That was confirmed by Mr. Chetouaae, an official of the French aid agency, Solidarite.
"There was intense shelling and small arms firing every day," Chetouaae recounts. "The situation regarding food is very, very bad. They haven't had regular food supplies for three to four months."
UN officials say Bosnian Serb forces have refused to allow either UN military monitors or aid convoys through to the area. While the Bosnian Serb onslaught has stalled for now, there is little doubt it will resume with greater strength if the Bosnian government refuses in the current round of Geneva peace talks to accept the Serb-Croat plan for an ethnic partition of the republic.
Western television footage has shown huge numbers of Bosnian Serb reinforcements pouring into the area and preparing large concentrations of heavy artillery and mortars.
Like Siber, Abdurahmanovic stresses that the Bosnian Army's ability to hold Mt. Igman depends on its ammunition stocks. "I don't know if we can keep Igman," he says. "But I think we will have to because it must be held at any price."