** FILE ** Passengers check in for their flights at Domodedovo Airport outside Moscow in April 2010. An explosion on Monday, Jan. 24, 2011, ripped through the arrivals hall at the airport, the city's busiest, killing at least 31 and wounding 130 others, Health Ministry officials said. The state RIA Novosti said the explosion may have been caused by a suicide bomber. (AP Photo/Misha Japaridze)

Photo by: Misha Japaridze

** FILE ** Passengers check in for their flights at Domodedovo Airport outside Moscow in April 2010. An explosion on Monday, Jan. 24, 2011, ripped through the arrivals hall at the airport, the city's busiest, killing at least 31 and wounding 130 others, Health Ministry officials said. The state RIA Novosti said the explosion may have been caused by a suicide bomber. (AP Photo/Misha Japaridze)