A boat carrying suspected migrants from Afghanistan and Syria sank Monday just north of the Bosphorus Strait off the coast of Istanbul, leaving at least 24 people dead. A further 12 were believed to be missing, while seven were rescued, Turkish authorities said. Coast guard vessels, divers and passing fishing boats were scanning the waters for more survivors. Twelve children were believed to be among those on board, AP quoted the coast guard as saying in a statement. It was unclear what caused the vessel to sink or where it had set sail from.