Gulf Air unexpectedly announced the resignation of its CEO, Andre Dose ending the former Crossair and Swiss International Air Lines CEO’s tenure less than four months after he joined the Bahrain-based carrier.

The announcement came just days after Gulf Air chairman Mahmood Hashim Al Kooheji disclosed that the airline was being investigated by Bahrain prosecutors.

The airline said its COO, Bjorn Naf has been named acting president and CEO and that the search for a permanent replacement had started. The airline added that a modernisation was being funded by an US$825 million infusion from its owners, the governments of Bahrain and Oman.

However, Oman has signed a letter of intent to withdraw its holding later this year, leaving Bahrain as the sole owner.