| Good for them. String the Islamicist bastards up. |
The violence followed a day of protests by tens of thousands of citizens demanding an end to the armed groups.
The bases include the HQ of the Islamist group Ansar al-Sharia, suspected of involvement in an attack on the US consulate in the city. Witnesses say supporters of Ansar al-Sharia lined up outside its headquarters, in front of the crowd, waving black and white banners. They fired into the air to try to disperse the protesters, but fled with their weapons after the base was surrounded by waves of people shouting "no to militias".
Buildings and a car were set alight and fighters evicted.
However, in a standoff outside the headquarters of the Sahaty Brigade in the city, three people were killed and at least 20 injured according to witnesses and officials. Another person was killed and another 20 injured in other incidents, city hospitals said.
The BBC's Rana Jawad in the capital Tripoli says the Sahaty Brigade is believed to be operating under the authority of the Ministry of Defence. Officials in Tripoli have been appealing for calm, she says.
Senior Libyan officials say that while they welcomed the protests, people should differentiate between the rogue militias and honest rebel brigades that helped to secure the town in last year's uprising against Col Muammar Gaddafi.
Earlier, some 30,000 protesters marched through Benghazi calling for an end to the armed groups and a return to the rule of law. Thousands of Libyans in Benghazi marched against the presence of militias. There has been a wave of hostility towards the militias since US Ambassador Chris Stevens and three others Americans died in the 11 September attack on the Benghazi consulate.
| Maybe there is an ounce of sanity in Benghazi... |
Many Libyans have expressed outrage at the attack on the US consulate, which followed a protest triggered by an anti-Islam film made in the US.
Libya's interim government has since come under renewed and intense pressure to rein in well-armed extremist militia groups and force them to disband.
Friday's march was the largest seen in Benghazi - considered the heartland of Libya's uprising - since Col Gaddafi was deposed.
Armed militia groups which helped to defeat Gaddafi remain powerful in many parts of the country. They are better armed and more numerous than Libya's official army, and there have been reports of militias intimidating and carrying out killings against rivals.
Earlier this week authorities in Libya arrested around 50 people in connection with the attack on the US consulate.