Flipping hamburgers was nothing like this: Creeping in the grass toward a Yugoslav army bunker; opening fire at the stroke of midnight at nearly invisible targets; crawling away amid the concussion and confusion of hostile mortar and artillery fire.

That was war in Kosovo for Jeton Jusufi, who in a year went from short order cook to guerrilla commando to conquering hero.

He is a Kosovo Liberation Army guerrilla who came down from the mountains today to visit relatives at this tiny, nine-house village in the woods of northeastern Kosovo. He was treated to a sumptuous feast -- a lamb barbecue near his burned-out house among admiring relatives who, like him, ran helter-skelter into the forests to escape a terrifying assault by Yugoslav army and Serbian special police forces.

Not long ago, Jusufi and other guerrillas were isolated by Yugoslav shelling, wild terrain and deadly suspicions. Now, KLA members patrol main roads and lounge publicly in cities. They have left their high country redoubts in Kosovo and havens in Albania as the Yugoslav military pulls out of the province.

NATO's goal of "demilitarizing" the KLA has not yet taken shape. The rebels are armed and uniformed, and their bureaucratic structure is being reorganized with breathtaking speed. The headquarters of one commander, named Remi, has been set up in a mansion in the hills of Pristina, Kosovo's capital. He has a press spokesman, and aides in well-pressed uniforms are taking requests for interviews.

Jusufi is still on road-patrol duty eight miles northeast of Pristina, and has yet to go into the city. "I will get to go eventually," he said. "Out here, the switch from war to peace hardly seems real. When we see the destruction, it is hard not to want to go and kill someone."

Until recently, survival was the KLA's main achievement. Jusufi acknowledged bluntly that the guerrillas had been on wobbly legs and that victory was made possible only by NATO airstrikes on the Yugoslav military and infrastructure.

"It was a catastrophe up here," he said as he sat among gaunt relatives in a field overlooking a picturesque valley. "We were on the defensive for months. We had to contend with our fleeing civilians. The Serbs were burning and stealing everything. We might have fought on, but only as a skeleton."

He walked to a field of upturned earth marked by perhaps 17 nameless wooden stakes. "Civilians were fleeing Podujevo over these hills," he said. "They were being shelled and sniped at. We found them lying all along the path. This is what we were up against."

Jusufi told his story with a mixture of pride, sadness and wonder that he made it out alive. He cursed the old rebel weapons -- mainly AK-47 rifles and some mortars -- that were no match for Yugoslav tanks and artillery.

His account, along with that offered by a rebel officer who happened by, matches in detail stories told by displaced ethnic Albanians who hid in guerrilla strongholds, and those of the troops and police who pursued them. It was a nasty hit-and-run war, in that the government security forces and sometimes the KLA targeted civilians.

A year ago, Jusufi, 21, was working at the Vokri hamburger shop in Pristina. One day, his uncle was arrested for poaching lumber, and Jusufi left his job to take care of his extended family. It was then that KLA recruiters persuaded him that he could escape both his poverty and policemen like those who arrested his uncle by taking up arms.

"We had lived with the Serbs for a long time, but they wanted to control everything," Jusufi said. "I thought we could win -- this was our land, we knew it well. So I joined."

He trained for six months in the mountains before he was sent in January to a front near the mixed ethnic Albanian-Serbian town of Vucitrn, 12 miles northwest of Pristina. His unit was assigned to attack troop positions protecting the road.

He took part in 15 such actions; as he described the first, in January, his stained teeth flashed with excitement: "It was near midnight. We crawled toward a house. We were no more than 200 meters away. At exactly midnight, we started shooting.

"I was scared and calm at the same time. We could see nothing, really. They shot antiaircraft guns toward us, but over our heads. I still can't believe I survived this." I don't know if I killed anyone. They didn't kill any of us."

This spring, the Yugoslav army's village-to-village shell-and-burn tactics sent civilians scurrying, many into the same mountains occupied by the rebels. "This created a problem for us," he said. "We felt we had to stand between the civilians and the army, and this cut our mobility."

When NATO bombing began on March 24, the army came with tanks and artillery and poured shellfire into the mountains. Army patrols also scoured the region for rebels, many of whom fled to Albania. The guerrillas lived off the meat of wandering cows. Civilians subsisted on corn and flour. Medical care for wounded rebels was rudimentary.

"We lost a lot of men because we could not operate on them," said Musli Spanca, 34, a rebel officer who was a karate teacher in Denmark before he joined the KLA last year.

Spanca insists, despite Yugoslav claims, that the KLA remained intact until the end. As for his adversaries, "I have nothing good to say about Serbs. They would surround the villages while militiamen burned them. They fired on civilians. There is nothing to praise."

CAPTION: Kosovo Liberation Army rebels march past burned out house after U.S. soldiers disarmed the rebels shortly before entering Kosovo city of Gnjilane.

CAPTION: Marines detain KLA rebels in Vladovo after taking their weapons. NATO moved for the first time to rein in the newly empowered rebels and allay Serbian concerns about possible rebel reprisal attacks.