Ms. Gonzalez was captured on video repeatedly meeting with Mr. Wilson in a vacant room inside the Metropolitan Detention Center, and she disclosed her pregnancy to jail officials in June 2012.

WSJ: Authorities Say Guard Had Sex With Murderer

Orkney Islands Council also uses its bunker as a meeting room and has kitted it out with video conferencing equipment.

BBC: Bunker mentality: The Cold War bunkers still in use