MOSCOW, Jan. 2 (Xinhua) -- Up to 21 people are confirmed dead in a household gas explosion in Russia, the country's emergency ministry said Wednesday.

The body of the 21st person was recovered from under the debris of the partially collapsed 10-story residential building, rocked by the explosion on Monday, the ministry said.

Fourteen of the bodies have been identified, and a search and rescue operation is still underway around the building in the city of Magnitogorsk, 1,400 km east of Moscow.

Wednesday has been declared a day of mourning in the region for those killed in the explosion.