Torture is widespread in Libyan detention centres run by brigades which emerged during the 2011 revolution, a UN report said Tuesday, urging Tripoli to bring all facilities under full state control.
"The report indicates that torture is widespread and most frequent immediately after arrest and during the first days of interrogation to extract confessions and other information," Ravina Shamdasani, a spokeswoman for the Office of the High Commissioner for Human Rights, told reporters.
"In some cases, members of the armed brigades freely admitted, and even tried to justify, the physical abuse of detainees," she said.
The authors of the report visited 30 centres over two years.
Libya's young post-revolution administration has made some efforts to revamp the prisons system but the estimated 8,000 people still held in connection with the conflict are under the control of armed brigades.
"The vast majority of the estimated 8,000 conflict-related detainees are also being held without due process," Shamdasani said.
The report recorded 27 cases of death in custody since late 2011 where torture was the likely cause, including 11 cases that took place in 2013.
"We recommend swift action to transfer detainees held by armed brigades to effective state control and renewed efforts to build the capacity of the criminal justice system," the spokeswoman said.
She said: "When detention facilities have been handed over to trained officers of the Judicial Police, there have been marked improvements in the condition and treatment of detainees."