PARIS -- The Paris prosecutor's office has opened a manslaughter inquiry into the May crash of an EgyptAir plane that killed 66 people, saying there is no evidence so far to link it to terrorism.

Prosecutor's office spokesman Agnes Thibault-Lecuivre said the inquiry was launched Monday as an accident investigation, not a terrorism investigation. She said authorities are "not at all" favoring the theory that the plane was brought down deliberately.

The decision to open the investigation was based on evidence gathered so far, she said, without elaborating.

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The French-manufactured plane, en route from Paris to Cairo, crashed in the Mediterranean May 19. Search teams have recovered its two flight recorders, which have not yet been analyzed. The reason for the crash remains unclear.

Egyptian officials had, however, suggested the most likely cause of the crash was terrorism, before backing off those remarks and saying no theories had emerged.

An Egyptian official at the ministry of civil aviation said Egyptian authorities haven't been notified of the French prosecutor's decision and that all scenarios remain on the table.

"There is no evidence that backs up or rules out any of the possible scenarios of what caused the crash, including whether it is a terrorist act or technical problems," he said.

The Egyptian investigation committee is in charge of issuing a final report, but France can also investigate because the plane was manufactured by France-based Airbus and French citizens were among those killed.

Egyptian investigators said earlier Monday that the black boxes from Flight 804 had arrived in Paris, where technicians were to attempt to repair them.

Both were extensively damaged when the plane crashed into the Mediterranean on May 19, killing everyone on board. The Egyptian investigators were unable to download information from the recorders.

In a statement issued late Monday, the Egyptian investigation committee said that the flight data recorder has been fully repaired.

The Egyptian investigation committee announced earlier this month that the flight data recorder from Flight 804 had been recovered from the bottom of the Mediterranean Sea, a day after the plane's cockpit voice recorder was also retrieved.