MOSCOW: A total of 14 security officers were killed in clashes earlier this week with militants in Chechnya's Grozny, the Russian Interior Iinistry said Friday, bringing the toll from the violence to 24.

"Fourteen policemen died during the counter-terrorism operation in Grozny," Russian agencies quoted a ministry spokesman as saying of the violence on Thursday.

Previously Russia's National Anti-Terrorist Committee said that 10 police and 10 rebels were killed as heavily armed gunmen stormed buildings including a school and exchanged fire with security officers.

Twenty-eight policemen were injured, with 12 airlifted for emergency treatment in Moscow. The ministry gave no new details on the injured policemen on Friday. The Thursday attack came on the day President Vladimir Putin gave his state of the nation address, and was seen by analysts as a demonstrative show of force by the insurgency which the Kremlin has spent years attempting to eradicate.

Authorities declared the counter-terrorism operation over on Friday after closing off the city centre on Thursday and deploying armed personnel carriers. A local market, a high-rise building housing media and a school were heavily damaged by fire and shooting.