A French investigating judge plans to travel to Malaysia as part of his probe into the fate of Malaysia Airlines Flight 370, deepening France’s involvement in the search for answers to the jet’s mysterious disappearance.

The move is likely to heighten scrutiny of Malaysia’s handling of its criminal investigation into the plane, which didn’t implicate anyone on board. France on Friday also joined the hunt for plane debris, starting patrols in the waters around Réunion Island, a French territory in the western Indian Ocean.

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