Stansted Airport said passengers were being taken off the Pakistan International Airlines plane.
A spokesperson said the passengers "will be taken to a reception centre on 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", they added.
More top news
Today marks the fifth anniversary of the royal wedding. Here we look at the highlights, in pictures.
A US citizen has been sentenced in North Korea to 10 years hard labour after being found guilty of spying.
Mohammed Moshin Ameen sent a stream of tweets glorifying Islamic State after his attempts to go to Syria were thwarted.