On the night of January 24, the Russian Federal Security Service (FSS) was checking information on a suicide bomber in Moscow region, Rosbalt reported with reference to law enforcers.

Journalists found out that the terrorist was hunted for not at Domodedovo airport hit by the blast, but in Zelenograd. The search yielded no result.

A criminal case has been opened over a suicide attack that hit Moscow's busy Domodedovo International Airport on Monday, killing at least 31 people and injuring about 130, RIA Novosti quoted a spokesman for the Investigative Committee of the Russian Prosecutor's Office as saying.

The blast occurred at about 04:32 p.m. Moscow time (13:32 GMT) at the international arrivals gate. Twenty of those injured were reported to have been admitted to hospitals in serious condition.

A suicide bomber was reported to have detonated himself in the crowd at the arrival gate.

The explosion was estimated to be equal to 5kg of TNT.