ROSTOV-ON-DON, September 15 (RIA Novosti) - Law enforcement officers have killed three militants in Nazran, the largest city in the Russian North Caucasus republic of Ingushetia, police said Tuesday.

"At about 23:40 Moscow time, three unknown men in a black Lada Priora car, whom law enforcement officers tried to detain, opened fire. They were killed by return fire," a police spokesman said.

Ingushetia and other North Caucasus republics, like Chechnya and Dagestan, have seen an upsurge of militant violence of late, with frequent attacks on police.

The Kremlin officially ended its anti-terrorism operation in Chechnya in April. The republic saw two brutal separatist wars in the 1990s and early 2000s.