Celebici, Bosnia-Herzegovina ? Black-masked NATO troops toting assault rifles descended on a remote eastern village on Thursday, setting off explosives, lifting carpets and checking behind a church altar in a failed search for the U.N. war crimes tribunal’s most-wanted suspect.

NATO said the raid on Celebici was conducted by a multinational force, members of the NATO-led peacekeeping contingent in Bosnia. Residents of the town, near the border with the Yugoslav republics of Serbia and Montenegro, said some of the dozens of soldiers who stormed their village from helicopters were American.

Although the sweep of Celebici did not turn up Bosnian Serb wartime leader Radovan Karadzic, NATO warned the former Bosnian Serb leader and other suspects not to relax.

“We are saying to Karadzic, ‘we are on your tail,”‘ said NATO spokesman Mark Laity.

SFOR, the NATO-led Bosnian Stabilization Force, said in a statement that the raid demonstrates NATO’s resolve in apprehending war crimes suspects.

Karadzic and Ratko Mladic, his top general, are charged with genocide and crimes against humanity in Bosnia during the more than three-year war that began in 1992 when the republic declared independence from Yugo-slavia.