ROME, July 21 (Reuters) - Italy's navy said it rescued nearly 1,800 migrants in overcrowded boats in the Mediterranean over the weekend, and a merchant ship recovered five bodies from a sinking rubber raft off the coast of Libya.
Calmer summer seas have led to a surge in people trying to reach Italy from North Africa. Italy has picked up more than 70,000 migrants so far this year in its search-and-rescue mission, called "Mare Nostrum" or "Our Sea".
The number of dead is also rising. At the start of July, the UNHCR estimated 500 migrants had died in the Mediterranean in the past six months, compared to 700 during the whole of last year.
A merchant ship rescued 61 migrants and collected five bodies from a sinking rubber raft late on Sunday after its position was signalled by the navy, said the force. Survivors said 15 others probably drowned.
Italy is struggling to keep up with the increase in migrant boats this year and has asked the European Union for more help in rescuing and housing them.
The U.N. refugee agency UNHCR said Maltese authorities on Saturday recovered the bodies of 29 people believed to have died from carbon monoxide poisoning in the hold of a boat.
On Friday, as many as 40 people went missing after a migrant boat capsized near the Libyan coast, according to media reports that the Italian navy could not confirm. A merchant ship recovered hundreds of survivors.
Most migrants have fled Syria's civil war and Eritrea's harsh military service, according to the UNHCR. Many of them set off for their journey to Europe from the coast of strife-torn Libya.
Italy's navy has been patrolling the waters between Africa and Sicily since October, when 366 people drowned after their boat capsized just a mile from the Italian coast.
(Reporting by Steve Scherer)