A witness told the investigating authorities that he had seen how the baggage of woman, dressed in black, exploded at the busiest international airport, reports said.
The eyewitness said that he saw the young woman in black robes and she had a bag or a suitcase on the floor next to her. Security agencies at the airport were aware of the possible terror attacks and looking out for "Black Widows' of the slain militants from Caucasus, who carried out suicide attacks in the past that include twin blasts in Moscow metro stations in March 2010.
Russia's National Anti-terrorism Committee (NAC) blamed lack of security measures in the airport as a cause for the blast.
The State police are looking for four men suspected of to be behind Monday's blast in the international arrival lounge of the Demodedovo International Airport. Police are said to have spotted the four suspected men on a CCTV footage.
The suicide blast perpetrators have been said to have taken the advantage of the absence of security check at the International Arrival"s gate and sneaked with explosives.
The power of the blast was between 5-10 kg equivalent of TNT,
spokesman Vladimir Markin said.