The Egyptian army says it has found wreckage of the missing EgyptAir flight 804, which crashed after disappearing from the radar while carrying 66 passengers and crew from Paris to Cairo.

According to the report published by the Wall Street Journal on Friday, automated communication systems aboard the jetliner sent warning alerts indicating a failure in the control system minutes before the aircraft crashed in the Mediterranean.

The report cited “people familiar with the matter” as saying that the smoke and the accompanying intense heat might explain why the pilot failed to communicate with air-traffic controllers just before the descent.

“We are looking into this report,” an unnamed Egyptian civil aviation ministry official told AFP. “At this point, I can't deny or confirm it."

Meanwhile, another report released by the Aviation Herald said that smoke had been detected in the toilet and the electric system prior to the crash. The flight data were received through the Aircraft Communications Addressing and Reporting System (ACARS).

Reports of a possible system failure came hours after the wreckage of the plane, including “personal belongings of the passengers and parts of the plane debris,” was found 290 kilometers (180 miles) north of Alexandria.

The aircraft, flying at an altitude of 11,300 meters (37,000 feet), crashed early on Thursday (local time) 10 miles inside the Egyptian airspace and killed all 66 people onboard.