Eleven people - including eight off-duty soldiers and two young children - have been killed, and 12 seriously injured, when the coach they were travelling in was blown up by a bomb.
The private coach was carrying more than 50 people and making its way from Manchester, along the M62, towards an army base in Catterick, North Yorkshire, when an explosive device in the rear of the vehicle detonated.
The explosion happened just after midnight on the eastbound carriageway between Chain Bar, near Bradford and Drightlington, south of Leeds.
It could be heard over an area of several miles and scattered bodies for 250 yards along the road.
The coach was carrying soldiers and their families who had been on a weekend break; some of the servicemen were travelling to RAF Leeming, near Darlington.
A family of four - Lance-Corporal Clifford Houghton, his wife Linda, who were both 23, and their two sons, Lee, five, and Robert, three - were among the dead.
'Open mind'
Army bomb disposal experts and police bomb squad officers have been sifting through the wreckage of the coach on the M62.
West Yorkshire police said: "We are treating this with an open mind. It could have been the work of terrorists."
The soldiers on the coach were drawn from a number of different regiments.
The coach was one of a number used to take soldiers on their weekend leave and return them to their bases.
Police have searched three other coaches bound for Catterick, which had left London, Liverpool and Leeds, fearing bombs could have been placed on board.
The injured have been taken to hospitals in Bradford, Wakefield and Batley.
A six-year-old boy has severe burns.
An ambulance official said: "You can't imagine a thing like this on a British road. How could it have happened?
"It must have been a bomb - and a fairly large one to create havoc like this."
Because of current industrial unrest among railway workers, soldiers with 48-hour passes have preferred to rely on coach services rather than trains to get them back to base on time.
