"The NGO rescue boat Sea-Watch says it does not receive any alerts of maritime distress from the EU's border agency Frontex, whenever the agency spots people in trouble in the Mediterranean."
NGO rescue boats do not receive Frontex alerts (EUobserver, link):
“Frontex would not alert civil rescue ships like Sea-Watch of any distress cases they find, as they know we would then take people to a safe port in Europe,” a spokesperson from the charity told EUobserver, in an email.”