TRIPOLI -- A boat carrying 74 people, mostly Sudanese, capsized off Libya on Sept 13, leaving only 13 survivors, the United Nations refugee agency (UNHCR) said on Wednesday, with dozens feared missing.

UNHCR extended condolences to "the families and loved ones of those who lost their lives" and called for an end to the conflict in Sudan, saying safe and legal migration pathways remain limited.

"The real solution is to end the war in Sudan so families can return home in safety and not take these dangerous journeys," the agency said.

The International Organization for Migration (IOM) said on Tuesday that at least 50 Sudanese refugees died after a fire broke out on the same vessel.

Separately, the Libyan navy said it rescued 35 migrants, including five women and a child, off the country's western coast on Tuesday. The group was picked up near Abu Kamash, about 156 km west of Tripoli, and taken to a reception centre where they received food, water, and basic services.

The navy said 51 smuggling cases had been recorded so far this year, with 3,480 migrants from various countries intercepted.

Libya has been a major transit point for migrants trying to reach Europe since the 2011 NATO-backed uprising that toppled Muammar Gaddafi. Smuggling networks have thrived amid political division and insecurity, exposing migrants to harsh conditions in detention centres and repeated Mediterranean shipwrecks.

The country remains split between the Tripoli-based Government of National Unity and an eastern administration allied with Khalifa Haftar's Libyan National Army.