Libyan citizens and military police have overrun several militia bases in the city of Benghazi following a major protest by residents against the power of unofficial armed groups.

Protesters stormed the base of the powerful Ansar al-Sharia militia, allegedly linked to last week's attack on the US consulate in the city. At least four people died in clashes at another militia base.

Hostility towards the militias has been running high since the attack on the consulate, in which the ambassador and three other Americans died.

The protesters are calling for the disbandment of the militias, many of which helped to topple Col Muammar Gaddafi last year but are now pursuing their own agendas.

The offices of the Ansar al-Sharia group were ransacked. Fighters at first tried to disperse the crowd but then fled as they were surrounded.

At least 40 people are reported to have been wounded in the clashes.