TRIPOLI/GENEVA (Reuters) - The United Nations criticised European countries on Tuesday for not allowing migrants to disembark at safe ports, as Libya’s coastguard said almost 500 migrants trying to reach Italy by inflatables had been brought back to the North African country.

The 473 people found trying to cross the Mediterranean on inflatables in different rescue operations since Saturday included some who were rescued by a cargo ship, coastguard spokesman Ayoub Qassem said.

U.N. aid agencies had earlier condemned the transfer of migrants to Libyan detention centres in which they often face abuse, lack of medical care, rape or forced labour, according to 61-page U.N. report in December.

“In Libya’s current context, where outbreaks of violence and widespread human rights violations prevail, no rescued refugees and migrants should be returned there,” Charlie Yaxley, spokesman for the U.N. refugee agency UNHCR, told a briefing.

Qassem said Tuesday’s figures included more than 140 migrants rescued at sea by the ‘Lady Sham’ cargo ship, whom the International Organisation for Migration (IOM) said were brought to the western city of Misrata and then to a detention centre.

Four people with burns were taken to hospital, while two others other died after having spent 24 hours at sea, Qassem said. The migrants were from different sub-Saharan and Arab countries and included nine children and 25 women.

The U.N. High Commissioner for Refugees (UNHCR) denounced “politicking around sea rescues” by European states that have restricted aid groups from conducting missions. More than 200 have already drowned in January and 4,507 have reached Europe by sea despite “bitter cold and great danger”, Yaxley said.

Libya’s western shores are the main departure point for thousands of migrants mainly from sub-Saharan countries fleeing poverty and conflict trying to reach Europe.

But since July 2017, smuggling networks inside Libya have been disrupted under an Italy-backed deal with local authorities in a former smuggling hub of Sabratha town in western Libya.

The coast guard has stepped up patrols after receiving new boats from Italy as part of efforts by the right-wing government there to stop migrants reaching Italian shores from Africa.

Migrants are bought to overcrowded detention centres that are formally under the control of the Interior Ministry but in reality are run by armed groups.