MOSCOW — An explosion rocked an international terminal of Moscow’s busiest airport on Monday afternoon in what Russian officials described as an apparent terrorist attack. The Health Ministry reported that at least 30 people had been killed and 130 injured, according to Russian state media.
Russian news agencies, citing witnesses, said the airport’s halls were filled with so much smoke that it was difficult to count the dead.
The blast occurred in the arrivals hall of Domodedovo airport, according to a spokeswoman. Investigators said the explosion occurred at 4:32 p.m. local time.
An eyewitness who gave his name as Yuri said the blast was intense and sent 200 people scrambling for safety.
“There were many people; if I were two meters to the side I would have been badly hurt,” he told the news channel Pervy Kanal. “There was a bang, and all I remember is that the shock wave pushed me to the floor. My hat flew away, and I put my jacket over my head. Five seconds later, when the smoke cleared, I saw people running out.”
Irina Tsvei, who was at the airport for a flight to Geneva, told the news channel that she saw the wounded being carried out of the airport and that the surrounding roads were jammed with ambulances and fire trucks.
In televised remarks, the Russian president, Dmitri A. Medvedev, said: “At Domodedovo an explosion has occurred, and according to preliminary information it was a terrorist attack. There are dead and there are wounded.”
He admonished officials for their failure to prevent the attack, and ordered the police to boost security at all airports and on public transportation.
International arrivals were being diverted to nearby airports, according to local news media reports.
The airport, southeast of the capital, is Russia’s largest airline hub, with more than 20 million passengers passing through last year.
If investigators find that the explosion was the result of terrorism, it would be the first such attack to hit Moscow since March, when two suicide bombers detonated explosives on the city’s subway during rush hour. More than 40 people were killed in that attack, which was traced to two women from Dagestan who had ridden buses into the capital.
The rebel leader Doku Umarov took responsibility for the March attack. In 2009, Mr. Umarov revived a suicide battalion linked to the most notorious attacks of the last decade. In a video apparently made hours after the blast, Mr. Umarov said “the war will come to your streets, and you will feel it in your own lives and on your own skin.”
In August 2004, two Chechen suicide bombers boarded separate planes at Domodedovo airport before killing themselves and 88 others in midair. The attack exposed holes in security at the airport: the two bombers, both women, had been detained shortly before boarding, but were released by a police supervisor. The authorities have since worked to improve procedures at Domodedovo.