While urging calm following Thursday's riots, Momcilo Krajisnik held out the prospect of more unrest against the NATO-led peace force.
"I hope you would repeat the same feat a hundred times over if we are in jeopardy, because we have the right to defend ourselves," said Krajisnik, the Serb member of Bosnia's tripartite presidency. He equated the presence of the peace force with an "occupation" of Serb regions in Bosnia.
On Thursday, U.S. soldiers in the NATO force fired tear gas and warning shots to fend off rock-hurling Serb mobs. Two American soldiers were injured in the clash, one of the most serious involving NATO peacekeepers since the Bosnian war ended.
Several civilians also were wounded. Roving mobs smashed the cars of international officials and roughed up foreign reporters.
Thursday's violence stemmed from the feud between Serb President Biljana Plavsic and supporters of Karadzic, the Bosnian Serbs' wartime leader and now the man most wanted by an international war crimes tribunal on Bosnia.
NATO said it took up positions in Brcko, Bijeljina and Doboj after receiving indications that forces loyal to Plavsic would try to take control of police stations and media in Serb-held areas of northern Bosnia.
In addition to U.S. troops, lesser numbers of Russian, Nordic and Polish peacekeepers patrol the region.
NATO has sided increasingly with Plavsic, the Bosnian Serb republic's elected leader _ and the only senior Bosnian Serb official who will honor the 1995 Dayton peace accords _ but said it also aims to prevent violence between the two factions.
Relations between the peace force and Karadzic loyalists have worsened markedly as international pressure has mounted to bring indicted war crimes suspects to justice.
The police, media and the military have broken into hostile camps loyal to one of the two dueling political leaders.
Bosnian Serb sources said several U.S. soldiers were hurt in a clash in the eastern village of Celopek that left cars burning. NATO officials did not confirm that.
The worst unrest was in Brcko, where NATO said a U.S. soldier was hit in the eye and had his nose broken.
Another soldier was lightly wounded, treated at a hospital for cuts and bruises and then released, said Lt. Cmdr. Karen Jeffries, a Defense Department spokeswoman in Washington. The other injured soldier remained hospitalized, she said.
State radio, loyal to Karadzic, incited the rioting, urging people to take to the streets and keeping tempers high Thursday. That _ plus the praise given the mobs by Krajisnik _ drew U.S. and United Nations condemnation.
"We will hold the parties' leadership responsible for keeping their people under control," said White House spokesman Joe Lockhart. He said the United States would not tolerate anyone "inciting people" against the peace force.
Brcko was calm by early today, with stores open and cleaning crews sweeping away shards of glass and other debris left by the rioting.
U.N. spokesman Liam McDowall said all 90 U.N. policemen in Brcko were evacuated by the NATO-led troops on Thursday, but one team had returned to assess whether it was safe for more to come back. Three officers were slightly injured Thursday when the main U.N. police station came under attack.
"All night long till the early morning hours, the situation was violent," he said. "You had mobs with sticks running around town, threatening."
Brcko sits astride a narrow Serb-held corridor, the only link between the two halves of Serb-held territory.
Plavsic controls the western section from her base in Banja Luka.
Karadzic controls the east from Pale, a village just east of the