Almost two months after Vietnamese troops conquered Phnom Pehn, Cambodia appears to have become a quagmire for its new rulers.

Honoi finds itself in the position of its one-time adversaries, South Vietnam and the Lon Nol government, unable to win active support from much of the population and struggling to build an administration with dubious success in the face of guerrilla opposition.

Much like the United States when it supported the South Vietnamese and Cambodian governments, Hanoi has trouble resupplying its forces because of destroyed bridges and mined roads that halt its now-mechanized army. In several towns, its forces are bottled up by the guerrillas, sources say.

In a larger context, Vietnam's invasion of Combodia and stationing of about 100,000 Hanoi troops to back a client regime in Phnom Penh have provoked a Chinese invasion of Vietnam. Peking has tried to link the withdrawal of Vietnamese forces from Cambodia to the eventual pullout of Chinese troops from Vietnam.

But for Cambodia, the Vietnamese conquest has brought a new step toward the destruction of a people already torn by five years of war. It ended in 1975 only to be succeeded by the mass murders and population transfers of the war's victors and today's guerrillas, the Khmer Rouge led by Pol Pot.

In western Cambodia, where Vietnam's supply lines are longest and its control tenuous to nonexistent, executions enforcing Pol Pot's control-by-terror tactics have resumed in the wake of Vietnam's troops, according to refugees who have fled to Thailand.

Pol Pot's troops and cadres ran to the jungles ahead of the Vietnamese advance, refugees say, but they told villagers they would return and in many places which they have reoccupied they have brought vengeance on those they accused of having been contaminated by the Vietnamese.

Men selected by the Vietnamese or in Vietnamese-sponsored elections to be village officials often have found themselves unprotected days or weeks later when the Vietnamese left and Pol Pot's men returned.

Echoes of the earlier Indochina war are abundant.

Village chiefs are murdered; marketplaces in supposedly Vietnamese-controlled areas are attacked; senior communist officials apparently don't travel around the countryside; villages have been taken, lost and retaken, and there are reports that some areas, particularly western Battambang Province, are being resupplied with food by air.

In some western districts, Vietnamese troops were conducting what the U.S. military once called search and destroy sweeps looking for Pol Pot units during January, but now they appear to keep to the towns, analysts say.

"In the west, it's like the last years of the Lon Nol government. In the east, the Vietnamese have somewhat more control -- it's like South Vietnam," one well-informed source said, drawing a parallel to former American-supported regimes.

No central government apparatus seems to be functioning under the regime of Heng Samrin, who was named Cambodia's leader after the Vietnamese invasion. Even the regime's own radio station can report no large organizing meetings or rallies of support.

It announced that political classes had begun in Phnom Penh evidently aimed at building up a new cadre of administrators. The radio said 107 people attended.

Three of the Vietnamese-installed regime's ministers held a meeting with medical personnel to plan health services, the radio said. They convened three doctors, one midwife and one medical student, according to the official report.

"If things had gone well, there would be photographs of crowds with flags and banners of welcome," one source said. "The absence isn't due to a lack of photographers."

It's also not due to the people's love for the brutal Pol Pot government, but rather to their fear, analysts say.

If the 100,000 to 150,000 Vietnamese troops in Cambodia could provide security, there are signs that they would be welcomed by a part of the population despite traditional Khmer-Vietnamese antagonism.

When Vietnamese entered western Cambodian villages, typically in units of 100 to 300 mem with several tanks and armored personnel carriers, according to refugees, they handed out cooking pots to allow people to eat in family groups if they chose instead of communally as the Khmer Rouge require.

The people were told they could rebuild their monasteries, practice Buddhism and traditional customs, marry as they pleased and that eventually they would have money again. Religion and money were abolished by the Khmer Rouge and forced marriage reportedly was common.

The changes were welcome, but the villagers noticed that only one or two Khmer speakers accompanied each Vietnamese unit and those often spoke the language badly or with an accent, raising the possibility they were ethnic Khmer from Vietnam.

Many feared Pol Pot's men would keep their promise and return.

Rang Phot, 26, told an interviewer in a refugee camp that she was jailed in 1977 for refusing to marry as ordered. She escaped from prison at Siem Reap when her guards fled the Vietnamese.

When she made her way to her village, she learned that the Pol Pot forces had warned they would return and kill anyone who had helped the Vietnamese.

She, like hundreds of other Khmer who have crossed into Thailand recently, chose not to take her chances on receiving protection from the Vietnamese.

Unlike Rang Phot, most had never been jailed. Non Loc, 76, for example, said he was asked by Pol Pot soldiers when they returned to his village to help persuade other villagers to come out of hiding and rejoin the commune. A big meeting was scheduled, he said.

He was frightened to be singled out and fearful of what would happen at the meeting. So he fled.

No one knows how much of Pol Pot's army survived the Vietnamese invasion. It took heavy casualties when it stood and fought near the eastern border last year. It had an estimated 80,000 members at its peak and informed guesses are that about 30,000 are left to fight the guerrilla war.

They have no chance of driving the better-armed, larger Vietnamese forces from Cambodia, but as one source put it: "Vietnam will have to bleed for a long time."

Even then Vietnam may never succeed in its effort to pacify Cambodia, although the French and American experience of Vietnamese persistence cautions against any prediction that they might quickly abandon their effort.

Gen. Van Tien Dung, who commanded the offensive that conquered Saigon in 1975, is believed to have led the invasion of Cambodia. He has written that taking Saigon was only the most extreme of several contingencies when the 1975 offensive was launched. Only when the speed and extent of South Vietnam's military collapse became evident did Saigon become the goal.

In Cambodia, once the Vietnamese army broke through near the Vietnam border, Pol Pot's forces seemed to disintegrate. Vietnamese troops raced through the country on main roads and took Phnom Penh in four days.

However, Pol Pot's troops were prepared. They did not fall back on cities -- which were largely emptied and never crucial to Pol Pot -- nor did their discipline fail.

As early as last summer, Pol Pot's defense minister spoke of fighting a guerrilla war. Food, arms and other supplies apparently were stockpiled in hiding places.