People gather at Dvortsovaya Square to commemorate victims of the air crash in Egypt in St. PetersburgIslamic State’s Egyptian affiliate dismissed in an audio message on Wednesday doubts that it had downed a Russian passenger plane over Egypt’s Sinai Peninsula, killing all aboard, and said it would tell the world how it did so in its own time. Sinai Province, an Egyptian group loyal to Islamic State, said in a statement the same day that it had brought down the airliner “in response to Russian air strikes that killed hundreds of Muslims on Syrian land”. The claim was dismissed by Russian and Egyptian officials.