Google "Five Eyes". The Wikipedia article has a bunch of sources to this particular issue in recent times.
Also, IIRC this has been talked about for a long time... I'm pretty sure I read about this practice initially in the 80s/90s, probably in reference to Libyan sponsored terrorism in Europe.
Also, IIRC this has been talked about for a long time... I'm pretty sure I read about this practice initially in the 80s/90s, probably in reference to Libyan sponsored terrorism in Europe.