Anti-aircraft gunfire and grenade blasts erupted in several parts of the Libyan capital Tripoli late on Thursday.
Reuters reported that the incident was the second time this week that the Libyan capital has been rocked by fighting between rival militia groups.
A security source told the news agency that a heavily-armed group had entered the capital to take revenge for one of its fighters who was killed in a shootout in Tripoli on Tuesday.
Two years after the fall of former strongman Muammar Qaddafi, militia that helped oust him now control large part of the North African country and regularly fight each other.
On Tuesday, reported Reuters, rival gunmen battled for hours on the capital’s streets. Three people were wounded and one later died, prompting the revenge attack, the source said.
On Thursday, fighters in a Toyota truck mounted with an anti-aircraft gun shouted “Allah Akbar” while driving at great speed near the foreign ministry.
Tracers from anti-aircraft guns could be seen marking targets in the eastern Suq al-Juma district and several other parts of Tripoli, followed by loud explosions, according to the report.
Shooting with rocket-propelled grenades could be also heard near the foreign ministry and state television building in a central coastal district.
Libya has been unstable since Qaddafi was overthrown two years ago. There have been several attacks in the country, the most well-known of which is the terror attack on the United States consulate in Benghazi.
Terrorists attacked the U.S. consulate on September 11, 2012, killing the U.S. ambassador and three other Americans.
Exactly a year later, a car bomb was detonated in Benghazi, damaging the exterior of Libya's Foreign Ministry building and the Central Bank of Libya.
Recent reports indicated that Al-Qaeda terrorists in Libya are trying to get their hands on a massive weapons arsenal that was left behind by the Qaddafi regime.
Qaddafi’s arsenal, which remains in an abandoned desert warehouse in southern Libya, reportedly includes 4,000 surface-to-air missiles, each capable of downing a passenger jet, and thousands of barrels of uranium yellowcake.