"I can't help wondering if those two fellows weren't traveling to Manchester for a particular reason."
Because that's where they live? This was a return journey, they weren't making a trip to Manchester, they were returning to there.
"This was a return journey, they weren't making a trip to Manchester,
they were returning to there."
Maybe it was a two-fer.
Get home.
Get home early enough for the big shindig.
It's an open question. They could have been perfectly innocent.
But given how friendly the current government of Spain is to the world of
Islam, if the police actually took them off and did all the extra sweeping
of luggage...maybe something didn't smell right to them as well.