Members of an armed group which had settled into a couple of villas overlooking the Mediterranean were evicted in the afternoon, the correspondent added.
Dozens of pick-up trucks blocked access to the Regata residential compound as members of the so-called National Mobile Unit of the army entered the complex to eject the militiamen.
An AFP correspondent witnessed from a distance as commanders of the brigade negotiated with the armed men who later were seen leaving the compound without putting up a fight.
"Our mission is to evacuate all public installations and private property occupied by groups who are not under state jurisdiction," Haj Musa, one of the commanders of the unit, later told AFP.
Earlier an army officer had said these operations would last two or three weeks.
On Saturday, the army issued an ultimatum ordering militias and armed groups to evacuate military compounds, state property and the properties of ex-regime members in and around Tripoli.
"All individuals and armed groups occupying military barracks, public buildings or property belonging to members of the former regime... (must) evacuate these sites within 48 hours," said the official LANA news agency.
Hundreds of former rebels have taken over strategic, state-owned military and civilian facilities and properties of supporters and relatives of the late dictator Moamer Kadhafi in the wake of his ouster and death last year.
The army warned it would "use force if necessary."
The Tripoli eviction comes hours after national assembly chief Mohammed al-Megaryef announced the decision to dissolve all militias that do not come under state authority.
Speaking in Benghazi, Megaryef said the authorities had decided to set up an "operations room" in the eastern city to include the army, interior ministry forces and defence ministry brigades comprising former rebels.
He also called on the army to place its own officers to head brigades born out of the 2011 revolt, which escalated into the civil war that toppled Kadhafi.
-- Crackdown follows murder of US ambassador --
The new authorities have been unable to disband or discipline these civilians-turned-fighters, though many units have joined the defence and interior ministries.
The crackdown comes after massive anti-militia protests in Benghazi on Friday and after an attack on the US consulate there sparked by a US-made film that mocks Islam left four Americans, including ambassador Chris Stevens, dead.
Megaryef said the rallies by Benghazi residents reflected a desire for "stability and security."
On Friday, hundreds of people stormed bases of militias sparking clashes that left 11 dead and dozens wounded. Fighting centred on the main base of Raf Allah al-Sahati, a Salafist brigade under the defence ministry.
Six members of the security forces were among those killed in the unrest that rocked Libya's second city. They appeared to have been executed, a medical examiner at the Benghazi Medical Centre told AFP.
Critics say militias in the eastern city have put themselves above the law, particularly those that refused to be placed under defence ministry authority.
Demonstrators first evicted a group based in a security building in central Benghazi before turning their wrath on the headquarters of Ansar al-Sharia, a radical Salafist militia.
Two hardline Islamist brigades in the city of Derna, famous for sending fighters to Afghanistan and Iraq, disbanded on Saturday, LANA reported.
The two brigades were the local branches of Martyrs of Abu Slim and Ansar al-Sharia, which has been accused of -- but denied -- involvement in the murder of the four Americans in the US consulate.
Megaryef initially welcomed the Benghazi protest, but as the violence expanded the authorities called on the demonstrators to distinguish between "illegitimate" brigades and those under state control.
The warning highlighted the dilemma facing the government, with the fledgling security forces dependent on former rebels who fought in the uprising despite such groups also challenging central authority.
The trigger for the assault on the paramilitaries was a "Save Benghazi" rally after the main weekly Muslim prayers on Friday that was attended by an estimated 30,000 peaceful demonstrators who paid tribute to Stevens.
The massive protest drowned out a smaller rally of a few hundred people called by the jihadists and hardline Islamists furious over the US-made film and cartoons of the Prophet Mohammed published by a French satirical magazine.