At least 45 migrants, including five children, have died in the deadliest shipwreck off Libya so far this year, the UN's agency for refugees says.

They were among more than 80 people on board a vessel whose engine exploded off the coast of Zwara, the UNHCR said.

The deaths were reported by some 37 survivors rescued by local fishermen.

Both the UNHCR and International Organization for Migration (IOM) called for search and rescue efforts to be stepped up.

They said that without a dedicated search and rescue operation mechanism, more lives would be lost in the Mediterranean.

The survivors were mainly from Senegal, Mali, Chad and Ghana.

bbc.com