MOSCOW — An explosion ripped through the international arrivals hall at Moscow's busiest airport on Monday, killing 35 people and wounding about 170, officials said. Russian President Dimitri Medvedev called it a terror attack.Israeli Ambassador to Russia Dorit Golender assured Foreign Minister Avigdor Lieberman that there were no Israeli's among the injured in the attack.Prime Minister Binyamin Netanyahu offered his condolences to the victims of the terrorist attack."The world needs to unite to defeat terror," he added, speaking in the Knesset plenum.The state RIA Novosti news agency, citing law enforcement sources, said the mid-afternoon explosion at Domodedovo Airport may have been caused by a suicide bomber. Those at the airport said it was filled with thousands of people at the time and the terminal filled up quickly with smoke."From the preliminary information we have, it was a terror attack," President Dmitry Medvedev told officials in a televised briefing.He ordered authorities to beef up security at Moscow's two other commercial airports and other transport facilities, including the subway system, the target of past terror attacks.Although there have been repeated attacks on the Moscow subway and Russian trains — most blamed on Chechen militants — the bombing Monday was the first involving a Russian airport since 2004.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."I heard a loud bang, saw plastic panels falling down from the ceiling and heard people screaming. Then people started running away," Lavochkin told Rossiya 24 television.Mark Green, a British Airways passenger who had just arrived at the airport, told BBC television he heard the huge explosion as he left the terminal."Literally, it shook you," he said. "As we were putting the bags in the car a lot of alarms ... were going off and people started flowing out of the terminal, some of whom were covered in blood.""One gentleman had a pair of jeans on that was ripped and his thigh from his groin to his knee was covered in blood," he added.Green said thousands of people were in the terminal at the time of the blast.Sofia Malyavina, a spokeswoman for the Social Development and Health Ministry, said 31 people were killed and about 130 were wounded. She said 56 ambulances were sent to treat the victims."The airport is filled with smoke," she said on Rossiya 24.Built in 1964, Domodedovo is located 26 miles (42 kilometers) southeast of the center of Moscow and is the largest of the three major airports that serve the Russian capital, serving over 22 million people last year.It is generally regarded as Moscow's most up-to-date airport, but its security procedures have been called into question.In 2004, two suicide bombers were able to board planes at Domodedovo by buying tickets illegally from airport personnel. The female bombers blew themselves up in mid-air, killing all 90 people aboard the two flights.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."Terrorists have previously targeted other transportation centers in Moscow.Twin blasts in the subway last March killed 39 people and wounded more than 60 people.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.