Seats from the Airbus jet that crashed in Egypt are examined by a Russian Emergency Situations Ministry employee, in this image released by the agency. Egyptian officials say they're investigating a noise heard at the end of the flight's cockpit voice recording. AP hide caption

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AP

Debris from a Russian airliner can be seen at the site of the crash in a mountainous area in Egypt's Sinai Peninsula. Citing new information, Britain's government says it is concerned that a bomb might have brought the plane down. Khaled Desouki/AFP/Getty Images hide caption

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Khaled Desouki/AFP/Getty Images

A woman mourns at a makeshift memorial for the victims of a jetliner crash outside Pulkovo International Airport in St. Petersburg on Tuesday. Vasily Maximov /AFP/Getty Images hide caption

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Vasily Maximov /AFP/Getty Images