Pakistan International Airlines spokesman Mashood Tajwar said the airline had been unable to contact the pilot of flight PK709, despite repeated attempts.
Mr Tajwar said the control tower at Manchester Airport had received a call about a threat on board the plane and the advised the pilot to divert to its sister airport of Stansted.
More top news
A Russian tourist has been fined 20 Euros (£15,829) for engraving a 10-inch tall letter 'K' on a wall of the Colosseum in Rome with a stone.
Ex-minister Owen Paterson said David Cameron should apply to leave the EU immediately after the general election next year.
Fresh data revealed smartphone and tablet users are increasingly targeted by online crooks.