A gas explosion has rocked a nine-story residential building in southern Russia, killing one woman, authorities say.
The blast in the town of Shakhty in the Rostov region early on January 14 destroyed four apartments on the top two floors, the Emergency Situations Ministry said.
Four people were still missing, the ministry said.
Rostov region Governor Vasily Golubev said two people were hospitalized, including a 2-year-old girl. The two were in serious condition, according to a Health Ministry spokesman.
A search-and-rescue operation involving about 120 people was being carried out at the site, the TASS news agency reported.
President Vladimir Putin "tasked the head of the region to provide comprehensive assistance to the victims," the Kremlin said in a statement.
Investigators said the accident came as a result of a gas explosion and that they had opened a criminal case into the matter.
The Investigative Committee said it was treating the incident as a gas explosion and was searching the offices of the company that was the gas supplier for the building.
The explosion follows a similar incident in the southern Urals city of Magnitogorsk on December 31, when an explosion sent a section of a 10-story building crashing to the ground.
Thirty-nine people died in the blast that authorities say was likely caused by a gas explosion.