An Italian diver who led a search for victims of a Mediterranean shipwreck has described the horror of finding the body of a baby, whose mother had clutched him to her as they drowned.

Rodolfo Raiteri, head of the coast guard divers, helped pull bodies from the Costa Concordia cruise ship which overturned off Italy in 2012, but said in an interview published Thursday that finding the baby on the seabed had been worse.

"The sight of that baby down there was unbearable, a blow to the heart," he told the Repubblica daily.

"You are never prepared for something as intense as that".

Raiteri's team had been looking for victims of a disaster on October 7, when a small, overloaded boat capsized off Italy's Lampedusa island. Only 22 of the 50 or so people on board were saved.

The bodies of 13 women, some of them pregnant, were recovered the day of the accident.

Bad weather hampered the search for the others, reportedly including eight children and other pregnant women.

"We were driven not only by duty, but passion. We could have given up... but we stubbornly wanted to continue searching, to give these people their dignity back. People, not 'migrants'," Raiteri said.

The team eventually traced the sunken vessel late last week.

'Held him tight'

Images filmed using an underwater drone show the wreck, with items of clothing lying nearby on the sea floor.

An underwater drone filmed the wreck
An underwater drone filmed the wreck GUARDIA COSTIERA / Handout

Other leaked photographs published in the Italian press showed bodies of those drowned floating eerily around the sunken ship.

Raiteri, 52, who has a two-year old daughter, said the moment that he and his team saw the images "tears came to our eyes".

"Seeing that little body lying on the bottom next to what was probably his mother was like a punch in the stomach.

"The fact they were so close to each other, and the way the arms of the woman were positioned, made us think she had held him close until the last," he said.

The International Organization for Migration (IOM) told the daily Corriere della Sera it believed it had tracked down the baby's aunt.

A survivor from Ivory Coast called Aminata had been on the boat with her two sisters and their children, but all four had gone missing.

She already identified one sister among the first bodies to be recovered, but was still looking for her four-year old nephew, as well as a second sister and her eight month old baby, it said.

Raiteri said bringing the bodies up from the seabed would not be easy.

"They are at a depth of 60 metres (200 feet), and we cannot last more than five minutes down there. So we'll have to be quick.

"We'll go down two at a time... and hope to be able to put the bodies in body bags on the sea floor, but that won't be easy because of the condition they are in. If not, we'll have to use ropes," he said.

The baby and his mother will be the first to be recovered, he said.