Police and security agents faced off in the violence-ridden republic of Ingushetia on Sunday after security agents shot and killed a local man, police officials and witnesses said, according to AP. Circumstances surrounding the latest bout of violence in the troubled North Caucasus republic were unclear, but it highlighted the persistent problem of intense distrust, and sometimes open clashes, between competing law enforcement and military units in the region _ some of whom operate under shadowy lines of command. Ingush Interior Ministry spokesman Yakhya Khadziev denied Russian and Ingush media reports that law enforcement units had clashed with agents from the Federal Security Service, or FSB, in the town of Karabulak, about 35 kilometers (20 miles) east of the regional center, Nazran. «An FSB operation was carried out against militants. One militant was killed, one detained,» he told The Associated Press. Local police and riot units then arrived on the scene to detain the agents and take them to a local police precinct, the officer said. Later, Defense Ministry soldiers in armored personnel carriers arrived at the police precinct and detained several riot police officers, the duty officer and witnesses said.