The pitted, rusty span isn't the only bridge across the Ibar River in this sagging industrial city, but it might as well be. To the north live some 20,000 Serbs; to the south, four times as many ethnic Albanians. Eight French soldiers stand between, just barely keeping a lid on things.

There is perhaps no starker symbol of the persistent ethnic divide in Kosovo than this one bridge in this one city. Five weeks after NATO forces entered Mitrovica, which was half in flames and largely deserted, up to 800 antagonists line up nightly on each side of the bridge to hurl rocks, slurs and whatever else is at hand.

On several recent nights, NATO peacekeepers have had to fire in the air to forestall a riot. The French needed 200 soldiers in armored personnel carriers just to escort a bus carrying 50 Serbs to an Orthodox church and cemetery in the ethnic Albanian quarter.

Although French officials see hope in the handful of ethnic Albanians who ventured into the Serbian sector last week, many of those who have done so say they have been beaten and stoned once they stray far from the bridge. "They punched me and threw rocks at me," said Bashkim Kutlouci, 12, pointing to fresh stitches on his chin and bruises on his cheek and neck. "They should be removed from there, all of them."

Those on the other side, who constitute the largest remaining concentration of Serbs in Kosovo, say much the same. Zivorad Ficitovic, 77, stood with his black trousers touching a coil of barbed wire that separates the bridge from the south side of Mitrovica. A retired farmer and factory worker, Ficitovic said he had come as far as he was willing to go without an armed escort to check on his apartment on the ethnic Albanian side.

"I'm afraid I'll be attacked by those terrorists," he said, referring specifically to the Kosovo Liberation Army guerrillas and generally to ethnic Albanians. "The soldiers have just told me to go, but I'm afraid to go on my own." Ficitovic eventually turned around and walked back to the other side.

Before the 78-day NATO bombing campaign forced Serb-led Yugoslav troops to withdraw from Kosovo, the city was a factory center of about 110,000 that garnered much of its wealth from the nearby Trepce mine complex. About 80 percent of the population was ethnic Albanian, and most of the rest were Serbs, mirroring the prewar ethnic makeup of Kosovo, a province of Serbia, Yugoslavia's dominant republic.

The French soldiers who patrol Mitrovica say they are doing their best to keep the situation under control, pointing out that no killings have been reported since they arrived here last month. But they have been unable to solve the standoff on the bridge and say they do not have enough troops to escort all who want to cross.

"The worst enemy we have here is fear: Both communities are frightened of each other," said navy Capt. Bertrand Bonneau, spokesman for French forces here. "What we are trying to do is cool things down between the two sides. . . . But we cannot work miracles. All the antagonisms of the communities are crystallized on that one bridge."

The standoff has been complicated by the uneasy relationship between the French and many ethnic Albanians, who allege that French soldiers are more sympathetic to Serbs. Bonneau said he has heard the opposite complaint from Serbs but added that the 150 troops stationed on each side of the bridge are trained to treat both sides fairly.

"The main problem in Kosovo is the problem right here in Mitrovica," said Tamer Krasniqi, an ethnic Albanian who said he has been unable to return to his boyhood neighborhood on the north side of the bridge. "This is apartheid, a ghetto, right in the heart of Europe. . . . Either we will sort things out, or we will kick the bastards. I think it will be the latter."

On the Serbian side of the bridge, dotted with modern high-rises in contrast to the low-rise dwellings on the southern side, a group of regulars sit in vigil blaring Serbian music and quizzing all who venture by. One woman said she was kicked out of her apartment on the other side of the Ibar by ethnic Albanians with guns, and she hasn't been back for 20 days.

"I don't have anything with me, and I don't know if I have anything left on the other side," said the woman. "There are no Serbs living over there anymore. We will all leave here eventually."

CAPTION: A French officer stops an ethnic Albanian from crossing to the Serbian sector of Mitrovica, a city that reflects ethnic antagonisms throughout Kosovo.