Russian media are reporting a shootout in the capital of the restive North Caucasus republic of Chechnya.

State news agency RIA-Novosti cited law enforcement sources as saying three police officers were killed in the city of Grozny when they attempted to stop a car carrying a group of gunmen.

The agency said the gunmen later barricaded themselves inside a publishing house.

Life News, a news outlet believed to have links to Russian security services, cited law enforcement officials as saying about 15 people seized three cars late Wednesday in the village of Shalazhi and drove them to Grozny. RIA-Novosti reported only on a gang of three people.

Unrest is common in Russia's North Caucasus, although forceful security measures have spared Grozny of significant violence for several years.