Spain's maritime rescue service says it has rescued 240 people but one person apparently drowned while trying to cross the Mediterranean Sea from North Africa.

The service says Sunday that its agents spotted a body floating underwater after their rescue ship had saved 41 migrants from a sinking smugglers' boat.

In all, the service says it rescued the 240 people from 11 small boats attempting the perilous crossing from African shores to Spain between Saturday and Sunday.

The U.N. says at least 660 migrants have died crossing the Mediterranean so far this year. Through the first four months of 2018, a total of 22,439 migrants reached European shores, with 4,409 of them arriving in Spain.