Egyptian investigators say black boxes to emit signal until June 24

The black boxes from an EgyptAir jet that crashed in the Mediterranean last month will continue emitting a signal from beneath the sea until June 24, a statement from the Egyptian investigation committee said on Monday.The investigation committee on Monday approved a request by the United States' National Transportation Safety Board (NTSB) to join the investigation team, the statement said.Investigators have confirmed that the EgyptAir jet tuerned sharply in mid-air before disappearing off radar screens, the statement added.