Breakthrough in attack on Russian jet?

Reuters:

Exclusive: EgyptAir mechanic suspected in Russian plane crash

An EgyptAir mechanic whose cousin joined Islamic State in Syria is suspected of planting a bomb on a Russian passenger plane that was blown out of Egypt's skies in late October, according to sources familiar with the matter.
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But the sources, who declined to be identified because of the sensitivity of the ongoing investigation, said the mechanic had been detained, along with two airport policemen and a baggage handler suspected of helping him put the bomb on board.

"After learning that one of its members had a relative that worked at the airport, Islamic State delivered a bomb in a handbag to that person," said one of the sources, adding the suspect's cousin joined Islamic State in Syria a year and a half ago.
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The Egyptians are still being officially closed mouth about the investigation.  The ties to ISIL who claimed credit for the crash could have broader consequences for both Egypt and Russian responses to the alleged terror attack.