A bomb explosion ripped through the mosque before gunmen opened fire on the people inside.
VASILY MAXIMOV via Getty Images
No group immediately claimed responsibility for the attack.
The "Wilayet Sinai", or Sinai Province (SP) offshoot of ISIS, took credit for downing a Russian-owned Metrojet airliner on 31 October. All 224 passengers flying from Sharm el-Sheikh to St Petersburg died in the crash. In its self-congratulatory tweet, SP referred to those killed as "Russian crusaders". Curiously, if SP reports to the ISIS nerve-centre in Raqqa, why target Russia at all? The US-led Operation Inherent Resolve has been far more damaging to the group's activities in Syria and Iraq than recent Russian airstrikes.