GROZNY, September 13 (RIA Novosti) - Two policemen were killed in an attack by unidentified assailants in a town 16 km east of the Chechen capital of Grozny, the North Caucasus republic's interior ministry said on Sunday.

The attack occurred late on Saturday in the center of the town of Argun when at least two gunmen opened fire with automatic rifles from a car at a police checkpoint, the ministry said.

Over 150 spent cartridges were discovered at the crime scene. Efforts are under way to find the attackers, the ministry said.

Chechnya, like neighboring republics Dagestan and Ingushetia, has 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.