At least 35 people died and 180 were injured in the attack at Moscow Domodedovo Airport when a bomb detonated Monday near the baggage claim in the international arrival area. Unconfirmed reports indicate a female suicide bomber was accompanied by a man who was beheaded by the blast, RIA Novosti reported.
Russian authorities said a suspected ''black widow'' could be behind the bombing. A witness told investigators he saw a woman dressed in black next to luggage that exploded, the Interfax news agency reported.
"The eyewitness declared that the young woman was dressed in black and the explosives were in the bag or suitcase on the floor next to her," a source close to the investigation was quoted as saying.
A "black widow," or shahidka, refers to Islamic Chechen female suicide bombers reputed to be part of a suicide-bomb force called the Riyad-us Saliheen Brigade of Martyrs.
A law enforcement official told RIA Novosti that airport security and police personnel "turned a blind eye to the presence of unauthorized persons."
Russian President Dmitry Medvedev also blamed the attack on a security lapse, saying airport officials should be held accountable.
A spokesman for Domodedovo, Moscow's busiest airport, said the facility's staff "acted strictly in line with aviation security requirements."
A police official told RIA Novosti the security services knew terrorists were plotting an attack on a Moscow airport, but couldn't locate and detain three suspects.
Medvedev said he instructed the Federal Security Service, known by the initials FSB, to determine which agency personnel were responsible for security at Domodedovo and instructed the Interior Ministry to introduce proposals on how to prosecute those who failed to ensure proper security.
"The FSB management must deal with issues of responsibility of officials in the service itself. I entrust the FSB director to submit proposals," Medvedev said. "I entrust the Interior Ministry to submit proposals for the dismissal or other prosecution of the ministry's officials responsible for transportation security."
Domodedovo was the site of a terror attack in August 2004, when two Chechen suicide bombers boarded separate planes killing themselves and 88 others in flight.