The pilots of an EgyptAir Airbus that crashed in the Mediterranean in May are reported to have battled to extinguish a fire.

Data from the cockpit voice recorder, revealed by sources close to the investigation but not yet made public, backs up evidence from the flight recorder of smoke in the cabin, the BBC reported.

Recovered wreckage also showed signs of high temperature damage and soot on the front section of the aircraft.

All 66 on board died when flight MS804 from Paris to Cairo crashed on May 19.

Both of the so-called “black box” recorders reinforce the automated electronic messages sent out by the aircraft that had shown smoke detectors going off in a toilet and in the avionics area below the cockpit, minutes before it disappeared.        

No distress call was made from the plane prior to the crash.

Egyptian investigators have not ruled out any reasons for the crash, including terrorism, particularly as such catastrophic fires on passenger planes are so rare.

The data recorders had been taken to Paris after being found, and the cockpit voice recorder was in need of considerable repair.

Investigators are still analysing the voice exchanges and no official statement has yet been made on the contents.