The busiest airport in Russia’s capital, Domodedov airport has been shaken by an explosion.
There was reportedly 31 people killed by the explosion.
Reports are suggesting that the explosion, that has injured more than 100 people, was the work of a suicide bomber.
The Chief Investigator has said the expolsion was the work of terrorists.
President Dmitry Medvedev has vowed the attackers would be tracked down.
The airport is 40km (25 miles) south-east of the city centre.
In the aftermath of the explosion, Mr Medvedev ordered an immediate increase of security to High Alert and Moscow police were ordered to survey all transport links for suspicious behaviour. An emergency meeting with top officials was called.
Initial reports indicate that the blast hit the baggage reclaim area of the international terminal.
A RIA Novosti news agency correspondent at the scene reported that a lot of smoke could be seen in the area, and there was a smell of burning.
Those responsible for the explosion will be tracked down and punished Russian President Dmitry Medvedev
The emergency services were rushed to the airport to tend to the wounded.
The UK Foreign Office has confirmed it is checking if any Britons were caught up in the incident.
British witness Mark Green, who had recently landed on the British Airways flight that landed at the airport shortly before the explosion. He told BBC News there were thousands of people gathered in the area at the time of the blast.
“We were walking out through the exit of the arrivals hall towards the car, and there was this almighty explosion, a huge bang, we didn’t know it was an explosion at the time, and my colleague and I looked at each other and said ‘Christ that sounds like a car bomb or something,’ because the noise was, literally, it shook you,” Mr Green told BBC News.
His witness account described scenes of mass panic and how he gave water to a bloodied Russian man, who had a soot covered face.
This comes less than a year after the Russian capital’s underground system was attacked by two female suicide bombers last March, who detonated their explosive devices on the metro system during a busy rush hour, killing 40 people and injuring more than 80 commuters.
Russian President Dmitry Medvedev has said in a televised briefing that “from the preliminary evidence we have, it was a terror attack”.
The President has also delayed his departure for the World Economic Forum in Davos, Switzerland.
Did you witness this explosion? Do you know someone who may have been in the airport? Please comment below