A Hampshire Constabulary spokesman said they were anxious to contact the people on other coaches which had dropped passengers at various places on their way south, including Portsmouth, Bulford, Barton Stacey, Tidworth, Aldershot, Bordon, and Middle Wallop.
The bomb blasted the rear of an army leave coach on the M62 near Batley, throwing bodies on to the road and strewing wreckage for 200 yards.
In total, 11 people were killed and 14 others injured, one of them critically.
One of the prime suspects was the Provisional IRA, after its announcement it would be stepping up its terror campaign in England.
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‘Nearly 300 people must have travelled south,’ the spokesman said. ‘We would like all of them to get in touch with their nearest police station as soon as possible.’
The appeal followed a request to Hampshire from Manchester CID.