At least 200 of the migrants made their way to a center for processing resettlement cases set up in Tripoli by the U.N. refugee agency (Unhcr), where they were seeking access, the agency said.
Reuters reporters saw the migrants near the center surrounded by guards and covering their heads from heavy rains, about two hours after residents started posting photos of the migrants walking through the streets.
It is still unclear why the migrants had been released from the detention center or where they might be transferred. Officials could not be reached and journalists were not allowed to speak to the migrants.
The International Organisation for Migration (IOM), another U.N. agency, said 600 had been released from the Abu Slim center. “Their safety is of major concern as armed clashes continue in Tripoli,” it said.
Tripoli has been hit by renewed violence since April when the eastern-based Libyan National Army (LNA) began battling forces aligned with the Tripoli government for control of the capital.
Migrants have been repeatedly caught in the crossfire during clashes in Tripoli, and Abu Slim is located in the south of the capital, close to the front lines. Heavy artillery fire could be heard from the center of the city on Tuesday.
Several thousand migrants are held in detention centers officially run by the U.N.-backed government because it receives funds from European countries to block migrants to go further northwards.
In practice, the centers are controlled by armed groups and there is widespread human rights abuse inside them, according to migrants, aid works and rights defenders.
Libya, with an estimated migrant population of 640,000, has been one of the main departure points for migrants trying to reach Europe. Boatloads of migrants leave frequently from Libya’s north-western coast, though the number attempting the crossing has dropped sharply since mid-2017 under European pressure.
Recently, several detention centers have been closed after human rights abuses were disclosed to the public and rights organizations, and migrants intercepted at sea by Libya’s EU-backed coastguard have reportedly been freed rather than being taken to detention centers.
The Unhcr center, known as the Gathering and Departure Facility (GDF), has been plagued by problems since opening late last year.
More than half of the 880 migrants at the GDF entered “informally”, some after fleeing another Tripoli detention center hit by an airstrike that killed more than 50 in July, UnhcrSpecial Envoy Vincent Cochetel told Reuters last week.
“Recently, the GDF has been severely over-capacity, leaving us unable to utilize it for its original purpose of evacuating people of out harm’s way,” he added.