http://www.bbc.com/news/uk-28873051
Reports are that the Brit was fighting alongside ISIS fighters and actually took the head off the US journalist. There are reports that the Brit confused James Foley with Axel Foley (a character from a US movie Beverly Hills Cop II) who basically is a bad ass cop who has no discipline and screws everything up.
Axel Foley was also in Beverly Hills Cop I (the first movie).