Four people have been killed and at least five wounded in a gufight which erupted earlier in the centre of Tripoli. The clash centred on an old intelligence building ealier bombed by Nato in the uprising against ex-leader Muammar Gaddafi. A brigade from the city of Misrata tried to release prisoners held inside, leading to a clash with another armed group from Tripoli. The casualties were from both sides. The firefight broke out near the building between Zawiya and Saidi streets, Bbc.co.uk reported.