“I don’t think we know yet” what caused the crash, Obama told CBS affiliate KIRO Radio.
“Whenever you’ve got a plane crash, first of all you’ve got the tragedy, you’ve got making sure there’s an investigation on site. I think there is a possibility that there was a bomb on board. And we are taking that very seriously.”
An investigation is underway to find out how the disaster happened; however, the airline has said that technical faults or human errors could not have caused the tragic incident.
An Egyptian militant group affiliated with Daesh terrorists said on Saturday it brought down the plane "in response to Russian airstrikes” in Syria. But Russian officials say it's too early to tell what caused the crash.
On September 30, Russia began its military campaign against militants in Syria. Moscow has carried out scores of airstrikes, killing hundreds of terrorists.