ASSOCIATED PRESS WRITER

BRANKA KOSTOVKA

ZAGREB, Croatia (AP)—Croatian mines wounded four French peacekeepers, sparking a bitter protest Sunday from the commander of U.N. forces in former Yugoslavia.

Two of the French soldiers were wounded Saturday when a mine exploded in the Medak region of southern Croatia, a U.N. statement said.

Canadian and French forces who came to the rescue in armored personnel carriers were fired upon by Croatian troops, and two more French soldiers were wounded when one of the vehicles hit another mine, the statement said.

‘‘It is indefensible for U.N. peacekeepers to be attacked by the parties whom we are here to help,’‘ French Gen. Jean Cot, the U.N. commander, said in a protest to Croatian Gen. Janko Bobetko.

‘‘It is even more incomprehensible when peacekeepers are engaged in medical evacuation,’‘ he added.

Croats are unhappy with the U.N.’s role as a buffer between them and the Serbs who captured a third of Croatia in a 1991 conflict following Croatia’s declaration of independence from Yugoslavia.

Croatia demanded last week that the U.N. leave by the end of November if it doesn’t begin meeting its mandate to disarm paramilitary groups and ensure that hundreds of thousands of refugees can return home.

That mandate expires Thursday, but talks on an extension are under way.

About 3,000 Croats in Zagreb protested Sunday what they called U.N. inefficiency. They built a wall of 8,500 bricks, each bearing the name of someone missing from Croatian towns, next to the U.N. headquarters.

U.N. officials say tensions between Croats and Serbs have soared since Croatian forces attacked Serbs in the Serb-held region Sept. 9 and captured several villages.

Serbs retaliated by shelling Croatian cities. The Croats withdrew Sept. 15 under a U.N. agreement but virtually destroyed the captured towns as they pulled out. Many of the Serb corpses they returned were mutilated.

In neighboring Bosnia, U.N. officials reported heavy mortar fire Sunday in Vitez, about 35 miles northwest of Sarajevo, which is mostly controlled by Croats.

Croatian radio said five civilians were killed and 11 others wounded in shelling by government forces. There was no confirmation of those figures.

U.N. spokesman Cmdr. Idesbald Van Biesebroeck reported sporadic small arms and mortar fire between Croats and Muslims in the southwestern city of Mostar.

In the Croat-held town of Medjugorje, Croats and Muslims signed a U.N.-brokered agreement to exchange prisoners of war, said Vlado Pogaric, an adviser to Bosnian Croat lear Mate Boban. Details were not immediately available.