Six people were injured in an explosion near a Moscow subway station that Russian officials say was caused by a leaking gas canister.
The Investigative Committee says two people injured in the December 22 blast were hospitalized.
The blast occurred in an underground passageway near the Kolomenskaya station, southeast of central Moscow, Emergency Situations Ministry officials said.
They said the canister was being used by welders doing repairs in the passageway.
The explosion caused a fire that authorities said was quickly extinguished.
Moscow Metro officials say part of the station was closed after the explosion.
Blasts in or near the Moscow metro cause concern because terrorists have targeted stations and subway cars in deadly attacks in the past.