Migrants arriving on boats in southern Italy say 81 other people travelling with them have died or gone missing during their sea journeys from north Africa, the UN refugee agency said yesterday.

A group of 27 migrants picked up on Tuesday by Italy’s naval rescue mission and brought to the town of Catania said there had been 75 other people on their boat, who were feared drowned, the UNHCR said in a statement.

Other migrants arriving in Sicily’s Porto Empedocle said two of the party they travelled with had died and four had disappeared.

Authorities said the death toll on another packed fishing boat, discovered by an Italian rescue mission on Monday, had reached 45. The victims are believed to have suffocated.

All those found dead on Monday by the Mare Nostrum or Our Sea naval operation were men from Subsaharan Africa, the UN said.

The UNHCR says around 500 migrants have died so far this year in the Mediterranean. Many were fleeing war in Syria, forced conscription in Eritrea, or poverty in other countries in Africa.

Italy’s navy tweeted that Mare Nostrum had rescued 236 migrants, including 35 women and 54 minors, yesterday.