Benghazi was the stronghold of the Western-backed revolt that eventually ended Gaddafi's hold on power in Libya.
However, Britain has not had any diplomatic presence in the city since an attack on the US mission last September that killed American ambassador Chris Stevens and three of his colleagues.
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Armed police have carried out a raid apparently linked to Wednesday's deadly terror attack in Westminster.
Cheryl Grimmer vanished from inside a beach shower block in Wollongong, Australia, in 1970, when she was just three.
Pc Keith Palmer was on the front line and because of his actions, the Westminster attacker was unable to kill anyone else.