At some point, he joined the INLA, an Irish republican and Socialist paramilitary group.
[5] The INLA claims that it was trying to halt the sale of illegal drugs in the local working class community.
[6][7] On 6 October 1999, Campbell, Declan Duffy and another INLA men captured the drug gang members in a warehouse in Ballymount Industrial Estate in Walkinstown.
Campbell failed to escape and was brought back to the warehouse and tortured by the other gang.
[5] He was buried with full military honours in Milltown Cemetery in Belfast by the INLA who staged a show of force including a uniformed colour party.