By Steve Scherer

ROME, June 1 (Reuters) - A dead baby plucked out of the sea whose picture sparked international outrage this week was probably a six-month-old Somali boy whose mother also most likely died in the shipwreck, Italian police said on Wednesday.

Like the photograph of the three-year-old Syrian boy Aylan lying lifeless on a Turkish beach last year, the image put a human face on the more than 9,000 people who have died in the Mediterranean since the start of 2014.

The baby was pulled from the sea last Friday by a German rescuer working for humanitarian organisation Sea-Watch after a wooden boat carrying more than 400 migrants capsized and sank some 58 km (36 miles) off the Libyan coast.

Sea-Watch immediately handed the boy's body over to the crew of the Vega, an Italian navy ship. The Vega brought 135 survivors and 45 bodies recovered after the shipwreck to the southern port city of Reggio Calabria on Sunday, including those of three small children, two boys and a girl.

Sea-Watch said it had distributed the photograph of the baby because it wanted to persuade European authorities to ensure safe passage to migrants after at least 700 were feared to have drowned in three separate shipwrecks in the Mediterranean last week.

"The photograph corresponds with the corpse of a six-month-old boy, who survivors of the shipwreck said was from Somalia," a high-ranking police official told Reuters on Wednesday.

"Survivors we talked to said the mother was not among the bodies recovered," he said.

There were discrepancies among the survivors as to the boy's name, which remains a mystery, he said.

Police arrested two men, a Syrian and a Moroccan, who were among the survivors of the shipwreck brought to Reggio Calabria on Sunday, accusing them of disaster at sea and international people smuggling, according to a statement.

A third man from Sudan, who is thought to have been the captain of the vessel, drowned, migrants told police.

The severely overcrowded wooden fishing boat described by survivors as "old, decrepit, un-seaworthy" and carrying no life jackets or floatation devices left late last Thursday from Sabratha, Libya, police said.

A leak developed in the hull and from there "water poured in and the vessel sank, leaving no escape for any of the many migrants below deck, nor for those unable to swim," the police statement said. (Reporting by Steve Scherer; Editing by Gareth Jones)