Take him prisoner and ship him to Gitmo, just in case.
Why Spain... He could seek asylum here in US once ZER0 is President. He could find a house in Hyde park where he will really feel at home with all other friends there..
So AQ kills 190 and injures 2,000 in Spain in March 2004 at some train stations, and they are asked by UBL to take in sonny-boy? Wow!!!! I guess terrorism is really paying off!