The Russian President Dmitry Medvedev blamed lax security for the suicide bomb attack that took place at arrivals hall of the Domodedovo airport in Moscow, Russia, which killed at least 35 passengers and injured more than 100.
A suicide bomber detonated a bomb that contained the equivalent of 7kg (15lb) of TNT at around 1330 GMT on 24 January.
At the time of the attack, the hall, which is accessible to non-passengers, was packed as several international flights, including one from the UK, had just landed.
Thick drops of blood and pieces of shrapnel were scattered across the snow-covered tarmac outside the hall.
The Russian President told prosecutors to probe security personnel at Moscow's Domodedovo Airport for possible negligence in allowing the bombing and ordered increased vigilance at airports and train stations.
All flights from Domodedovo have been suspended since the blast, while incoming flights are being diverted to Sheremetevo Airport, according to the BBC.
At least seven of the people killed were foreigners, including UK and German citizens, according to the Emergency Ministry website.