More than 200 migrants have been freed from a "secret prison" in the Libyan city of Kufra, where they were being held in inhumane conditions.
Two Reuters sources in Libyan security structures said authorities had discovered an underground prison, almost three meters deep, which they said was run by a Libyan people smuggler.
One of the sources said that the person has not yet been arrested.
"Some of the released migrants had been held in underground cells for up to two years," the source said.
Another source stated that what was uncovered during the operation was "one of the most serious crimes against humanity ever uncovered in the region."
"The operation resulted in the raid on a secret prison inside the city, where several inhumane underground detention cells were discovered," one of the sources added.
The freed migrants are from sub-Saharan Africa, mainly Somalia and Eritrea, and include women and children, the sources said.
Kufra is located in the east of the country, about 1.700 kilometers from Tripoli.
Libya, since the overthrow of Muammar el-Gaddafi in a NATO-backed uprising in 2011, has become a transit route for migrants fleeing conflict and poverty towards Europe, using dangerous paths across the desert and the Mediterranean Sea.
Libya's oil-based economy also attracts impoverished migrants seeking work, but the security situation in the country is poor, making migrants particularly vulnerable to abuse.
At least 21 bodies of migrants were found in a mass grave in eastern Libya last week, and up to 10 survivors from the group showed signs of torture before they were released from captivity, two security sources told Reuters.
Libya's chief prosecutor announced on Friday that authorities in the eastern part of the country had referred one defendant to court in connection with a mass grave, on charges of "committing serious violations of the rights of migrants."
In February last year, 39 bodies of migrants were recovered from about 55 mass graves in Kufra. The city is also home to tens of thousands of Sudanese refugees who fled the conflict that erupted in Sudan in 2023.
Bonus video:
