By Ghaith Shennib and Ulf Laessing
TRIPOLI (Reuters) - Heavy fighting between militias using rifles, grenades and anti-aircraft weapons erupted in several parts of Tripoli on Tuesday in the worst violence in the Libyan capital for weeks.
Fighting started in Tripoli's eastern Suq al-Juma district and a central area where two burned out pick-ups belonging to a militia on the government payroll could be seen. Libyan news websites said at least one person had been wounded.
The shooting started after a member of a militia was detained at a checkpoint after which fellow fighters arrived trying to free him, a militia source said.
Reuters reporters in Tripoli could hear shots from rocket propelled-grenades and anti-aircraft guns throughout the night. Tripoli was quiet on Tuesday morning but occasional rifle shots could still be heard.
OPEC producer Libya faces chaos and anarchy as the government struggles to rein in militias, gangs and Islamist radicals in a country awash with arms two years after the ouster of former leader Muammar Gaddafi.
Several security officials declined to comment when contacted by Reuters on the latest incident.
Officials are often reluctant to discuss militias which call the shots in the streets. Many technically work for the police or other regular forces but in practice report to their commanders.
Fighting between militias is often about personal arguments, control of local areas, stolen cars or smuggled goods such as drugs or alcohol banned in Libya.
Tripoli has been spared the assassinations and bombings that happen almost daily in the eastern city of Benghazi but the security situation is also volatile in the capital.
Several embassies have been attacked, while last month a group of former rebels briefly kidnapped Prime Minister Ali Zeidan before other militiamen freed him.
Separately, dozens of people protested on Monday night in Benghazi against the deteriorating security situation and recent killing of an intelligence officer and his young daughter by a bomb, residents said.
Protesters burned tires in several parts of the port city and demanded the government of Prime Minister Ali Zeidan and parliament quit.
Many in the oil-rich eastern part of the nation demand autonomy from Tripoli and a greater share of oil wealth.
On Sunday, an autonomous movement launched a shadow government in the east, a move that is sure to worsen ties with the weak central government, which has rejected the declaration.
A mix of strikes and protests for higher pay or more political rights has shut down much of Libya's oil output, depriving the government of its main source of income
(Reporting by Ghaith Shennib and Ulf Laessing,; Editing by Angus MacSwan)