SARAJEVO -- Bosnian government forces clashed with separatist Serbs for a second day Tuesday, United Nations officials said.


But the fighting, near Tuzla in the northeast, was not as fierce as on Monday when the Bosnian army launched a major assault.


"There is reduced fighting in the area today," UN Major Ronald Mansson said by telephone from Tuzla.


The Bosnian army suffered scores of casualties after launching the offensive Monday, a move that shattered a cease-fire that has been in place in the country since Jan. 1.


A UN official who visited a hospital near the fighting reported seeing at least 150 wounded among the mainly Moslem government forces.


Monday's fighting centered on the Majevica hills and on an area around the Serb-held Vlasic mountain overlooking the government town of Travnik in central Bosnia. There were no reports of fighting on the second front Tuesday.


The offensive prompted a strong Serb response. Bosnian Serbs launched artillery attacks on civilian population centers, shelling Tuzla and killing 19 and wounding dozens more, Moslem-controlled Sarajevo radio reported.


Lack of diplomatic progress toward a peace settlement in Bosnia has prompted Western fears that Moslems and Serbs are preparing for a return to war in the spring when the cease-fire expires.


In Paris, French Foreign Minister Alain Jupp? warned Tuesday of renewed fighting and urged greater international efforts to "avert the inevitable."