The first column of 80 Yugoslav trucks, cars, vans, buses, antiaircraft guns and ambulances emerged from their camouflaged hiding places at 11:45 this morning to begin a stoic retreat from the ruins of Kosovo.

At the head of the convoy was a sedan carrying Maj. Gen. Vladimir Lazarevic, commander of the Pristina Corps, which had spearheaded military operations in the territory. Before leaving Kosovo, Lazarevic briefly addressed his troops. "We did our job," the stocky commander said. "It is up to the United Nations force to do its."

Then they roared away from the land they had pledged never to abandon.

Across Kosovo today, a nearly invisible army came into the open. For 11 weeks, 40,000 soldiers and policemen had been scattered across the countryside in small groups, the better to pursue separatist ethnic Albanian guerrillas and avoid annihilation by NATO jets. Tanks were disguised as haystacks, armored cars as trees. Fuel trucks were festooned with rugs, missile launchers buried.

That changed today under a hot sun. Flatbed trucks awaited cargoes of tanks and artillery pieces near the city of Kosovska Mitrovica. A convoy of five buses and six trucks ferried blue-clad policemen from the city. Troop trucks crisscrossed Pristina, the battered provincial capital, picking up soldiers for the pullout.

At sunset, a strange, somber parade of another sort hinted at the legacy the Serb-led Yugoslav forces are leaving behind: 110 ragged prisoners from Lipljan prison marched into Pristina on their way to homes in Podujevo, 27 miles to the north. They had been given only bags of onions to sustain them on the trek. Some of the men were skeletal and had to be supported by companions. They said the prison was closing.

Despite a suspension of NATO bombing and the evidence of an orderly withdrawal of Yugoslav troops and Serbian police, it did not seem for many Pristina residents that peace was at hand. Even this small initial troop withdrawal left an immediate security vacuum here and stirred undisguised fear among both ethnic Albanian and Serbian citizens about their future.

In Podujevo, ethnic Albanians closed themselves in their homes as government security forces left the city. These people, once among 600,000 internally displaced ethnic Albanians, had remained in Kosovo wandering the countryside, hiding in woods and abandoned villages, until they threw themselves on the mercy of the police and were allowed to return.

Having survived the torment of war, they now fear anarchy. Three houses owned by ethnic Albanians were burned overnight, adding newly charred remains to dozens of houses torched by police and soldiers during the height of the government's expulsion campaign. Danger lurked in the possible return of marauding Serbian paramilitary groups. For some ethnic Albanians, a renewed infiltration by the main separatist guerrilla force -- the Kosovo Liberation Army -- posed a threat: Would some of the ethnic Albanians who stayed behind be regarded a collaborators?

"We are worried about a lot of things," said Hasan Haydula. "When our neighbors return, they will be angry. And the KLA was here before."

Podujevo lies at the edge of one of the main KLA strongholds, a wooded, hilly area known as Llap. Driving the rebels from the region was one of the main objectives of the Yugoslav offensive in Kosovo. Ethnic Albanian villages stand empty for miles around; scores of the traditional walled and whitewashed Albanian family compounds are roofless and scarred by smoke from fires set within.

When reporters visited Podujevo today, many residents shut courtyard doors and windows at their approach. "It's dangerous for us; the police look unhappy, and when they are unhappy, we pay," said a 16-year-old in a baseball cap who ventured out to talk.

Residents said they had seen Serbian families pack up and leave before the troop pullout. Cars with trailers bearing ovens and refrigerators competed with the army in the race to leave Kosovo. "It will be hard to persuade them it is safe; it is hard for us to convince ourselves we are safe," said a teacher named Shukri Rexhepi.

Fifteen miles to the west in Kosovska Mitrovica, Serbian civilians watched the departing convoys of troops and police grimly. Community leaders have been urging them to stay, but the shift in the balance of power troubles them. Their greatest fear is a return of the KLA and its tactics of harassing Serbs.

"I have thought about leaving, but I have no place to go," said a white-haired battery-factory worker named Momo as he watched the military convoy idling on the highway. "For now I will stay, but I can't say I'm sure now that the army and police are leaving. Maybe the KLA will come back, and we will be kicked from our house."

Momo lives in a small, ethnically mixed neighborhood at the edge of Kosovska Mitrovica. His words of mistrust were poignant, for he is a rare hero in the Kosovo tragedy. According to neighbors, he single-handedly persuaded Yugoslav soldiers not to expel a number of ethnic Albanians from their homes. "We will never forget what he did," said one ethnic Albanian resident.

Despite the tribute, Momo is fearful. "I'm afraid of the Albanians, and unfortunately I don't know if I can really trust my neighbors if things get difficult," he said.

Momo, like most Serbs in Kosovo, regarded the government offensive in the province as a necessary assault on the separatist KLA. "They wanted to take over, and Yugoslavia had to fight back," he said. "The burned [ethnic Albanian-owned] stores were a result of anger. It just happened. The Albanians who come back will be angry. So where will that leave me?"

For Serbian police, plans for a pullout from Kosovska Mitrovica were mixed with apprehension about family members. Most policemen in Kosovo are local residents. Leaving their relatives behind was out of the question. "Would you?" an officer named Nebojse asked a visiting journalist.

Kosovska Mitrovica is one of the most battered towns in Kosovo. Before the conflict, it sheltered a hard core of Serbian nationalist militiamen and was repeatedly infiltrated by KLA guerrillas. Shootouts and terror were common.

Ethnic Albanian neighborhoods stand empty and silent; a community cemetery outside town bears more than a dozen anonymous graves. Wooden markers list only numbers and the date 05-06-99. There was no one around today who might explain how these people died.

After the NATO bombing began on March 24, Serbian police and militia units rampaged through the main ethnic Albanian commercial district. Dozens of businesses were ransacked and set afire. A mile-long strip of ruined stores from the mosque to the entrance of the city attests to days of terror.

Nebojse, the policeman, blamed the destruction on combat and on unidentified local Serbs who were angry at having lost friends and relatives to the KLA. "We don't deserve this," he said of the war and its outcome.

He declined to discuss Yugoslav government policy in Kosovo, where ethnic Albanians had complained of second-class treatment. "I'm a policeman, not a politician," he said. "I want to come back and expect that the U.N protects us all. I don't believe it, but that is my hope."

He said police would abandon Kosovska Mitrovica precinct by precinct and that the process would probably take the entire 11 days alloted by NATO for a full withdrawal from Kosovo. "Frankly, I don't know what I'll do in Serbia. Maybe you can get me a visa to the United States. I hear there is a lot of police work that needs doing there," he said.

In general, the withdrawal appeared to be orderly. The mundane tasks of moving out began early in the morning. Soldiers took boxes and boxes of documents and paperwork from a command post hidden in a Pristina apartment building. The men carrying them off joked about ripping off their unit patches and replacing them with KLA badges.

Yugoslav army officials put a conditionally brave face on the retreat. Lazarevic said in an interview that his soldiers had guaranteed that Yugoslavia would remain whole by defending Kosovo against NATO and separatist Albanians.

The commander of the Pristina Corps predicted the KLA would create problems for the peacekeepers and blamed NATO, whose airstrikes in western Kosovo helped the guerrillas make inroads. "The U.N. troops will have to think about this," he said.

The convoy rolled north, past the ruined ethnic Albanian stores that line the highway and the empty houses and fallow fields beyond. In the distance, smoke coiled from a walled courtyard; a house was aflame. Some soldiers in the convoy flashed the three-fingered Serbian victory sign.

CAPTION: Troops wave from a truck about 15 miles north of Pristina. The truck was part of a convoy carrying at least 2,000 Yugoslav soldiers out of Kosovo.

CAPTION: A convoy of vehicles carries U.S. Marines on along a highway toward the Macedonian capital, Skopje. The Marines, who are to become part of the allied peacekeeping force in Kosovo, entered Macedonia from Greece.