The aid group Save the Children said Tuesday that 400 people may have drowned this week in a capsizing off the Libyan coast, based on its interviews of survivors who arrived in Reggio Calabria in southern Italy. Italy’s coast guard helped rescue 144 people on Monday and has found nine bodies but said a higher toll was likely. The deaths, if confirmed, would add to the skyrocketing numbers of migrants lost at sea. The International Organization of Migration estimates that more than 3,000 migrants died in the Mediterranean in 2014, up from 700 in 2013.