Rome, July 10 (IANS/AKI): The Italian coastguard recovered the bodies of at least 12 migrants and rescued some 500 others off the Libyan coast, reports said on Friday.

Coast guards responded to an SOS call late on Thursday and plucked the migrants from four packed boats. The 12 drowned migrants were found inside one of the boats, which was almost completely submerged.

The two Italian coastguard patrol boats set sail from the southernmost island of Lampedusa after receiving the distress call and located the four boats in the Mediterranean, about 60 nautical miles north of the Libyan coast.

Coast guards continued to search the area but no further survivors or bodies were reported to have been found.

On May 29, an Italian navy vessel intercepted a boat that had set sail from Libya with 217 people on board and found the bodies of 17 dead migrants inside the boat's hull.

An estimated 150,000 migrants have reached Europe by sea so far in 2015, most of them Greece and Italy, while over 1,900 have drowned in the Mediterranean, twice the toll during the same period last year.

Most of the people making the perilous boat journeys are refugees seeking protection from war and persecution in Syria, Africa and Asia, according to the UN.

The European Union boosted search and rescue operations in the Mediterranean in late April after a migrant boat sank off Libya with the loss of over 800 lives, one of the worst maritime disasters since World War II.