An explosion ripped through the international arrivals hall at Moscow's busiest airport on Monday, killing at least 35 people and wounding about 130, an airport spokesman said.

Russian news agencies reported the explosion was caused by a suicide bomber and that the device was packed with shrapnel.

"From the preliminary information we have it was a terror attack," President Dmitry Medvedev told officials.

Medvedev said the explosion demonstrated that security regulations had been breached and ordered Moscow police to beef up security at Moscow's two other commercial airports and other key transport facilities, including the subway system, the target of past terror attacks.

Sergei Lavochkin, who was waiting in the arrivals hall for a friend to arrive from Cuba, said he saw emergency teams carrying bloodied people out of the terminal.

Sources tell Fox News the U.S. intelligence community also is investigating the Russian bombing. Two U.S. officials said no conclusions have been reached about the bombing or the individual or group behind it.

Domodedovo is generally regarded as Moscow's most up-to-date airport, but its security procedures have been called into question.

Currently 77 airlines offer regular flights to Domodedovo, serving 241 international and national routes, according to airport's website.

The airport insists that security is one of its top priorities, claiming on its website that its "cutting-edge operations technology guarantees the safety of passengers' and guests' lives."

Twin blasts in the subway last March killed 39 people and wounded more than 60 people.

Chechen rebel leader Doku Umarov claimed responsibility for that attack, warning Russian leaders that "the war is coming to their cities."

In December 2009, Chechen rebels claimed responsibility for blowing up a high-speed train between Moscow and St. Petersburg, an attack that killed 26 people and injured scores.

NATO Secretary-General Anders Fogh Rasmussen said he was "deeply disturbed" by the reported terror attacks.

"I strongly condemn it," he said on Twitter. "NATO and Russia stand together in the fight against terrorism."