The Paris prosecutor's office on Monday opened a manslaughter investigation into the crash of EgyptAir flight MS804, as the doomed jet's black box memory chips were sent to France for repair.
The Airbus went down in the eastern Mediterranean Sea en route from Paris to Cairo on May 19 and all 66 people on board were killed. The cause of the crash remains unknown.
"The Paris prosecutor has opened today a full investigation into involuntary homicide," the prosecutor's office told Reuters in a text message.
The prosecutor said it was not looking into terrorism as a possible cause of the crash at this stage.
Damaged memory chips from the black boxes were flown to France on Monday after Egyptian investigators had tried without success to repair them, an investigation committee statement said.
The chips should allow investigators to begin transcribing and analyzing the recordings and data which may hold key insights into what caused the crash.
A lab belonging to France's BEA air accident investigation agency will try to remove sea salt deposits from the chips before returning them to Cairo for analysis.
The plane is believed to have crashed in the deepest part of the Mediterranean and the black boxes, recovered last week, were badly damaged.
On Monday debris from the jet was brought to Cairo airport, where investigators will try to reassemble part of the plane's frame in search of additional clues that may help explain the crash, a source on the investigation committee said.