Talks Fail to Remove Threat of Civil War in Yugoslavia : Republics: Meeting between rival leaders of Serbia and Croatia yields no progress. U.S. sees ‘a significant danger of violence.’

ZAGREB, Yugoslavia —  The rival leaders of Communist Serbia and pro-independence Croatia broke up a meeting Friday with no reported progress in their efforts to pull the country from the brink of possible civil war.

The army said late Friday it had arrested a number of unidentified people accused of organizing and arming illegal groups that planned an uprising and “terrorist acts” on soldiers, their families and military facilities.

The nation’s official Tanjug news agency said two officials of Virovitica, a town about 60 miles east of Croatia’s capital of Zagreb, had been arrested by a military patrol. Official sources in Zagreb said up to 10 Croats were detained by the military.

Croatia’s interior minister said his non-Communist republic would welcome foreign assistance in case of attack by federal armed forces. The republic has bolstered its own police force to counter such a move by the army.

Tanjug said Serbian President Slobodan Milosevic and his Croatian counterpart, Franjo Tudjman, had met in Belgrade for talks that “dealt with the future of Yugoslavia and relations between the two republics.”

“It has been concluded that relations between Serbia and Croatia are at their lowest point since World War II,” the officially released statement said.

It also said that “there are significant differences of views about national questions, the future of Yugoslavia, the Yugoslav federation . . . and the Yugoslav army.”

The confrontation in Yugoslavia pits federal authorities and Serbia, who favor retaining a strong federal system, against the non-Communist governments of Croatia and Slovenia, who want a loose alliance of sovereign states.

Threats and counterthreats reached a peak Thursday, when federal armed forces in Croatia and the republic’s own special police forces both were placed on battle alert.

The U.S. government Friday called for a dialogue to avert the “potential use of military force.” State Department spokeswoman Margaret Tutwiler said that “there is a significant danger of violence.”

The Communist-led collective federal presidency, which includes representatives from each of Yugoslavia’s six republics, met for an emergency session Friday.

In Zagreb, journalists of the Croatian news agency HINA described the meeting as “dramatic” without providing details.

Soon afterward, Bozidar Petrac, a close associate of Tudjman, said in Belgrade: “There is no need for panic among the Croatian people.” He said a statement would be issued later.

Earlier this week, the presidency said it would not use force to disarm illegal republican paramilitary groups it had ordered to surrender their weapons.

But the army, whose officer corps is heavily Serb and pro-Communist, on Wednesday announced it would move to disarm illegal groups in Croatia, saying forces in that republic were plotting attacks on the army.

“Croatia is faced with a possible military coup and army terror,” Tudjman had told an emergency Croatian Parliament session before flying to Belgrade.

An agreement between the Croats and Serbs, Yugoslavia’s two largest ethnic groups, is considered essential if the federation is to lay to rest its many disputes.

Secession would be far more difficult for Croatia than for westernmost Slovenia because it is home to a minority of about 500,000 Serbs that Milosevic has vowed to protect by extending his republic’s border if need be.

Croatia’s Parliament session was called to pass laws declaring the precedence of republican legislation over federal measures and to place the republic’s police forces solely under Croatian command.

Croatia has 20,000 men under arms. There are about 40,000 federal troops in Croatia and Slovenia.