A suicide bomber in the international arrivals hall at Moscow’s busiest airport has killed at least 35 people, including foreign nationals.
President Dmitry Medvedev postponed his visit to Switzerland where he was to attend the Davos meeting of the World Economic Forum.
Russian state television reported that more than 150 people, including European Union citizens, were injured in Monday's attack that bore the hallmarks of militants fighting for an Islamist state in the North Caucasus region.
Medvedev vowed to track down and punish those behind the attacks at Domodedovo Airport.
He added that he had delayed his trip to the 41st World Economic Forum (WEF) annual meeting in Davos where he aimed to promote Russia as a profitable investment haven to world business leaders.
Medvedev was due to fly to Switzerland on Tuesday to deliver the opening speech at the annual forum.
It is not clear whether he will address the Davos meeting or whether his stay in the Swiss mountain resort might be shortened.
A scheduled meeting between Medvedev and Swiss President Micheline Calmy-Rey at Zurich airport on Tuesday has been cancelled, according to the Swiss foreign ministry.
Swiss not affected
Moscow's Domodedovo Airport was closed briefly. A Swiss International Air Lines flight from Geneva landed normally at around 4pm.
“There is no word of any Swiss passengers or staff being affected,” Sonja Ptassek, a Swiss spokeswoman, told swissinfo.ch.
The Swiss foreign ministry said it had no information about possible Swiss victims.
A passenger of a Swiss flight to Moscow said he saw hundreds of police and ambulance vehicles at the airport.
Moscow police were put on high alert and immediately beefed up patrols in the subway system, a previous target of terrorists.
Domodedovo is generally regarded as Moscow’s most up-to-date airport, but its security procedures have been called into question.
No group has yet taken responsibility for the attack which raises new questions over security in Russia. The country is to host the 2014 Winter Olympics in Sochi and host the 2018 football World Cup.
In 2004, two suicide bombers were able to board planes at Domodedovo by buying tickets illegally from airport personnel. The bombers blew themselves up in mid-air, killing all 90 people aboard the two flights.
Built in 1964, Domodedovo is located 42 kilometres southeast of the centre of Moscow and is the largest of the three major airports that serve the Russian capital, serving over 22 million people last year.
Moscow suffered its worst attack in six years in March 2010 when two female suicide bombers from Dagestan set off explosives in the metro, killing 40 people.
Terror attacks in Russia
October 2010: Three suicide bombers attack Chechnya's regional parliament, killing six people.
March 2010: Double suicide bombings on the Moscow subway kill 40 and wound more than 100 others.
November 2009: Attack on a high-speed train Moscow-St Petersburg kills 28.
August 2009: Suicide bomber kills 25 in an attack on a police station in Ingushetia.
November 2008: 12 people killed when a suicide bomber hits a bus in North Ossetia.
August 2004: A suicide bomber blows herself up outside a subway station in Moscow, killing ten people.
August 2004: Two female suicide bombers bring down two Russian airliners that took off from Domodedovo airport, killing 90 people.End of insertion
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