Bangkok — Tensions and conflict in Indochina are sharpening. Vietnam's dry-season offensive in Kampuchea (Cambodia) is proving the most intense since the Vietnamese overthrew the Communist Khmer Rouge government six years ago last Monday.
At the same time, the Vietnamese now are claiming that a massive Chinese troop buildup is taking place on the China-Vietnam border. Contacted Tuesday, a Chinese official commented that his country's response would be ``the same as other years'' -- in other words, increased pressure on Vietnam's northern border.
Resistance at the major Khmer guerrilla base of Ampil had all but ceased by midday Tuesday, reports from the Thai border say. The camp, which houses the military and civilian headquarters of the Khmer People's National Liberation Front (KPNLF), was attacked Monday by a Vietnamese force now estimated to number 3,500 to 4,000. The 5,000 defenders, well dug in but lightly armed, apparently were no match for the tanks and artillery thrown into the battle by the Vietnamese.
The artillery was said to have been exceptionally intense. Thai officers say that more than 7,000 shells fell on the camp in the first day and a half of fighting. Guerrillas say the almost continuous barrage left them deafened and disoriented.
About 20 armored vehicles, 12 to 15 of them T-54 tanks, also took part in the attack. The guerrillas claim to have disabled six vehicles.
Since the Vietnamese offensive began on Nov. 18, nine refugee camps controlled by various members of the anti-Vietnamese Coalition Government of Democratic Kampuchea have been evacuated. More than 155,000 Khmer refugees are now in temporary shelters on the Thai side of the border, refugee officials say.
Intermittent fighting is now going on along almost the whole of the Thai-Kampuchean border. In the far north, diplomats report, a brisk engagement is taking place between Vietnamese and KhmerRouge troops at the so-called tri-border area, where Thailand, Laos, and Kampuchea meet. Along the central part of the border, north of Ampil, Thai troops say they are fighting to dislodge a Vietnamese unit which has intruded into Thai territory during its attack on O Bok, a KPNLF base. A Thai jet fighter was reportedly shot down there Tuesday with the loss of one crew member.
More fighting has been reported in the last week near the Khmer Rouge headquarters of Phnom Malai. And KPNLF spokesmen say that their forces are still fighting the Vietnamese around the remains of their other bases.
By far the biggest loser so far has been the KPNLF. Only one of their eight camps remains intact -- the purely civilian camp of Dangrek (pop. 17,000). The situation there, however, was ``tense,'' an aid official said Tuesday. KPNLF guerrilla losses have not been announced, but must run to a least several hundred dead.
The political damage to the KPNLF, however, may be less grievous. The Vietnamese hope that the loss of Ampil will destroy the Front's credibility with its Western backers. But diplomats from the Association of Southeast Asian Nations (ASEAN), one of the Front's firmest supporters, said that the loss of the camp would make no difference.
``They're not there to defend a camp,'' said one ASEAN diplomat. ``They're supposed to be guerrillas.''
If pressure became too heavy, the diplomat continued, the KPNLF would have to make a ``tactical retreat.'' This would affect neither their credibility nor their supply of aid from ASEAN or the West, he said.
``The most important thing is that they retain their forces and their supplies,'' he said. Though there were reports of exploding arms dumps in Ampil during the attack, the diplomat doubted that the KPNLF had lost many of their supplies. ``They've probably moved them to a safe place,'' he said, declining to suggest where the safe place was.
The Chinese may be less understanding. They have always had a certain disdain for the KPNLF. And they have tended to ask to see results before providing more weapons. They have supplied so far about three-quarters of the KPNLF's arsenal, including antitank weapons delivered during the fighting last month. If Peking showed any sign of reducing the weapons flow, however, it would probably come under intense pressure from ASEAN.
The attack may help resolve a debate that has long raged within the KPNLF, between proponents of all-out guerrilla war and those who advocate more conventional tactics. Some younger members of the KPNLF leadership have long expressed frustration with the strategy adopted by the military command -- the defense of highly visible and highly vulnerable fixed positions.
Most top military men, like Dien Dell, the commander at Ampil, are products of the French era. ``They're good at battalion-sized maneuvers,'' said one Western analyst today, ``but that's not what's needed.''
``The thinking of some of us is that the KPNLF cannot continue on the border,'' said Abdul Gaffar Peang Meth, the Ann Arbor-trained political scientist usually thought to be one of the leading KPNLF ``young turks.''
``We have to go inside the country and set up bases there. Right now our civilian and military camps are separate from each other,'' Mr. Gaffar said, ``but they are not far enough [apart] in my view.''
Gaffar and others want to create purely civilian camps near the border, and move guerrilla operations deep into the interior, and many Western supporters agree.