Black box reveals explosion

The sound of an apparent explosion can be heard on the flight recorder of the Russian plane that crashed over the Sinai in Egypt, killing 224 people onboard. This adds to the mounting evidence that a bomb was smuggled aboard, French media sources said on Friday.

The recordings give further credence to the idea that the plane crash was a terrorist act. Russia been resistant to speculation about a bomb, but has suspended flights to all Egyptian airports.

An Egyptian-led international team of aviation experts, including some from France, successfully recovered the black box, the flight recorder, from the crash site. Several French media outlets, including the television station France 2, reported that the investigators had listened to it and concluded that a bomb had detonated, which would seem to rule out structural failure or pilot error. The pilots can be heard chatting normally, including contact with airport controllers, up until the apparent explosion.

Russia had earlier said that the UK was acting prematurely in halting flights to the Red Sea resort over terrorism fears, ordering even wider restrictions on Friday, including halting all flights from Cairo.

Meanwhile, the US announced new security measures – including tighter screening – for flights from some airports in the Middle East. Jeh Johnson, the homeland security secretary, said that the move was motivated by “an abundance of caution”.

Russia initially dismissed claims by Islamic State of responsibility for downing the plane, which came weeks after threats of retaliation for Russian air attacks against targets in Syria, and Moscow reacted angrily after David Cameron said it was “more likely than not” a bomb.