The UN Libya mission said on Wednesday it was gravely concerned by reports of the sudden release of 401 prisoners and acts of retribution in the country’s western towns captured by forces of the Tripoli-based Government of National Accord (GNA) this week.

The statement came after forces aligned with the GNA seized the towns of Surman and Sabratha on Monday, pushing back the eastern-based Libyan Arab Armed Forces (LAAF) that has been trying to capture the capital for just over a year.

“UNSMIL [United Nations Support Mission in Libya] notes with grave concern reports of attacks on civilians, the Surman Prison break and release of 401 prisoners without adequate legal proceedings or vetting, desecration of corpses, and retribution, including looting, robberies, and torching of public and private properties,” the UN mission said in a statement.