Bart Jansen

USA TODAY

Traces of explosives have been found on some of the victims of the EgyptAir plane that crashed into the Mediterranean earlier this year, sparking a criminal investigation into the incident, Egypt’s Civil Aviation Ministry announced Thursday.

The crash of Flight 804 from Paris to Cairo killed all 66 people aboard on May 19. Investigators have said alarms heard on the plane’s recorders suggested sensors detected smoke in a lavatory on the Airbus A320 and problems with the cockpit windows. France opened a criminal investigation in June.

The latest announcement said "traces of explosive materials" had been found "on the bodies of victims" of the crash. Under a 1981 law, the discovery by the technical committee investigating the incident triggered a referral to the general prosecutor, the ministry announced.

Egypt moves to beef up airport security

Nobody has claimed responsibility for the EgyptAir crash. Its demise came after the Islamic State claimed responsibility for blowing up a Russian Metrojet flight on Oct. 31, 2015, from the Red Sea resort of Sharm El-Sheikh, killing 224 people over the Sinai.