A spokesman for Stansted Airport said passengers were being taken off the plane.
"They will be taken to a reception centre in the airport where police may wish to interview them about what they have seen. At some point police and the airline will arrange for their onward transportation to Manchester."
A Manchester Airport spokesman said:
"The plane - flight number PK709 - was travelling from Lahore and had 297 passengers on board. For further information for friends or family who were due to meet the flight at Manchester please call 0800 140 4007.
More top news
The body of Kester David was found in Broomfield Lane, N13 on Wednesday, 7 July 2010. Police believe he died in the early hours of that day.
Her partner was upstairs at the house at Basildon in Essex getting her hospital bag when the masked gang smashed their way in using crowbars
Drivers belonging to the RMT union are due to walkout at 9.30pm on Saturday in a dispute over a sacked colleague.