French civilian aviation authorities have grounded all planes of two small French Polynesian airlines.
Air Moorea and Air Archipel have had their operating certificate suspended after inspectors found irregularities in Air Moorea's maintenance procedures.
The grounding also applies to an Air Tahiti plane operated by Air Moorea in the Marquesas.
The authorities say the inspectors acted on rumours about maintenance problems.
They also say the suspension is not linked to the recovery of the wreck of the Air Moorea Twin Otter which crashed last month killing all 20 people on board.
The cause of the crash is yet to be established.