A gun battle broke out early today in the capital of Russia's North Caucasus republic of Chechnya, leaving at least three traffic police officers and six gunmen dead, authorities said.
The fighting punctured the patina of stability ensured by years of heavy-handed rule by a Kremlin-appointed leader.
Security officials and the leader of Chechnya said militants traveling in several cars killed three traffic police at a checkpoint in the capital of the republic, Grozny.
State news agency RIA-Novosti cited an unnamed law enforcement source as stating that five police officers were killed.
More than six hours after fighting broke out, Chechen leader Ramzan Kadyrov said a multi-story publishing house building the militants had occupied in central Grozny had been destroyed by fire and six of the gunmen had been killed.
He later said several other gunmen had been found in a city school and an operation was under way to "liquidate" them, the Interfax news agency quoted him as saying.
Although unrest is common across the North Caucasus, forceful security measures adopted by Kadyrov have spared Grozny significant violence for several years.
An Associated Press reporter saw the publishing house building in flames and heard the sound of heavy-caliber gunfire before dawn, several hours after the unrest erupted.
The Moscow-based National Anti-Terrorist Committee, a federal agency, said in a statement that security services, police and emergency services personnel had surrounded the publishing house building. The agency also announced that it had imposed a counterterrorism regime on the center of Grozny.
This officially allows heightened security measures to be enacted and the announcement typically indicates the imminent use of heavy force to quash unrest.
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, some 50 kilometers (30 miles) away.
Kadyrov said on his Instagram account, a social media website he regularly uses to issue public statements, that the traffic police officers were shot dead as they attempted to stop the cars carrying the gunmen.
Kadyrov said the situation was calm and that all essential public services would still be operating, but he urged Grozny residents to exercise caution.
"I ask residents in areas where (security) operations are being carried out to abide by safety measures, and not to go out onto the streets without cause or to go near their windows," he wrote.
"All the talk about the city being under the control of the military is absolutely false." Kadyrov said in a message posted several hours later that six militants were killed in the standoff at the printing house.
