A note was handed to the pilot of the plane who then reported the possible device on board, according to Manchester Evening News reports.
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Dominic Chappell, the man who bought BHS for £1 from Sir Philip Green, is to be prosecuted by The Pensions Regulator.
The 5,000 ecstasy pills had an estimated street value of £36,000.
Police say it is "too early" to know if the body is that of journalist Kim Wall, who is believed to have died on board an amateur submarine.