The disappearance of the Russian airliner which crashed in Sinai on Saturday was preceded by sounds in the cockpit “uncharacteristic of a standard flight”, according to Russian media.
The Interfax news agency quoted officials in Cairo as providing a first insight into audio recordings from the Airbus 321’s “black box” recorders.
They reported that after a period of routine discussions between crew members, “the recordings show sounds uncharacteristic of a standard flight precede the moment of the airliner’s disappearance”.
According to Interfax, the recordings also suggest “there was a sudden emergency situation on board which took the crew by surprise, and the pilots did not have time to send a distress signal”.
Confusion remains over whether the crash of the plane, which broke up in mid-air and sent debris across the remote and conflict-ridden region of Egypt, was caused by an internal fault, explosive device or external action.
On Monday evening, US intelligence officials told NBC News that an American satellite picked up a strong “heat flash” in the area at the time of the crash.
According to NBC, officials said the flash was not preceded by a heat trail from below – suggesting there’s no indication the plane was struck by a missile.
“The speculation that this plane was brought down by a missile is off the table,” the official said.
US officials pointed to an explosion on the plane itself as the most likely cause, but there is no way of telling from satellite images whether it was caused by a fuel tank or possible bomb on board.
Kremlin officials have not ruled out a terrorist attack on the plane, which was carrying 224 people at the time.
But speaking to BBC News, Egypt’s President Abdul Fattah al-Sisi said that Isis’s claim to have brought down the jet at 35,000ft was “propaganda”, and said the area of Sinai in question was under government forces’ “full control”.
Meanwhile, the US Embassy in Cairo has instructed its staff to avoid travel anywhere in the Sinai Peninsula as a “precautionary measure” until further notice.