A suicide bombing attack Monday at Moscow's Domodedovo International Airport killed at least 35 people. Russian President Dmitry Medvedev has ordered an increase of security at all of the country's airports and transportation hubs.

Yelena Galanova, the airport's press secretary, confirmed that the toll from the deadly blast has risen to 35, RIA Novosti reported.

At least 130 other people were injured in the blast that took place at the airport's international arrivals hall at 4.32 p.m. (1332 GMT).

While one report said the suicide bomber was present among the crowd at the international arrivals gate, eyewitnesses said there were two terrorists who blew themselves up as passengers emerged from the international arrivals zone around 4.40 p.m. (1340 GMT).

Tatyana Morozova, spokeswoman for the investigation committee, said the explosion occurred in the arrivals area around 4.22 p.m. (1322 GMT), Xinhua reported.

But a spokesperson for the Federal Customs Services (FTS) told Interfax news agency that the blast happened in the lounge area near the Asia Cafe next to an international departure area.

Interfax also quoted security sources as saying the suicide bomber was probably from the northern Caucasus region.

A criminal case has been opened over the suicide attack, a spokesman for the Investigative Committee of the Russian Prosecutor's Office said.

RIA Novosti quoted Medvedev as saying at an emergency meeting: "It is necessary to step up security at all airports, railway stations and transportations hubs. I order you, Transport Minister Igor Levitin, together with Interior Minister Rashid Nurgaliyev, to employ the relevant procedures in cooperation with the Federal Security Service."

Medvedev has pledged assistance to the families of the victims, and also announced he would postpone his visit to the Davos Economic Forum in Switzerland.

Law enforcement officials said the power of one of the blasts was equal to 5 kg of TNT and that the bomb was packed with metal objects to cause maximum damage.

Airport employees broke down the wall between the main airport and the arrivals zone to allow passengers to escape the scene of destruction.

Russia's Rosbalt news agency reported that the Federal Security Services (FSB) was aware that terrorists were planning an impending attack, but were searching for the criminals in Zelenograd town near Moscow.

Security has been tightened at other airports in the capital and the city's metro system, which was hit by deadly terrorist attacks in March 2010.

A law enforcement source said three men are wanted in connection with the bombing.

"According to intelligence, three men may have been involved in organising the explosion. They have been living in the region of the Russian capital for some time," the source was quoted by Interfax as saying.

Xinhua reported that Moscow's Sheremetyevo airport was accepting planes that were bound for Domodedovo.

All international flights to Domodedovo have been stopped. Security was tightened at other Moscow airports and on the capital's underground rail system.

DPA reported that Russian shares fell more than two percent in the wake of the bomb blast. Leading the fall in the Moscow Stock Market's Micex index was a more than five percent drop in shares in the Russian flag carrier Aeroflot.

Domodedovo is an international airport located in Domodedovsky district, 42 km southeast of central Moscow. It is the largest airport in Russia in terms of passenger and cargo traffic. Around 22.25 million passengers used the airport in 2010. It is one of the three major Moscow airports along with Sheremetyevo and Vnukovo.

In August 2004, two planes that took off from Domodedovo were blown up by female Chechen suicide bombers, killing a total of 90 people.