The stall-prevention system on a Boeing Co. 737 Max jet automatically switched on before the plane crashed in Ethiopia this month, the Wall Street Journal reported, citing initial findings from the plane’s flight data.

The conclusion was relayed at a briefing at the U.S. Federal Aviation Administration on Thursday and is the strongest indication yet that the same system malfunctioned in both the Ethiopian Airlines flight and the Lion Air disaster in Indonesia in October, the newspaper said.

A preliminary report from Ethiopian authorities is expected within days, though the preliminary conclusions — based on analysis of the aircraft’s black boxes — could still change, the people briefed on the matter told the Wall Street Journal. A representative for Boeing said the company was unable to comment on the investigation.

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