A boat captain who is held responsible for the April 2015 sinking of a boat that killed hundreds of people has been sentenced to 18 years in prison and a nine-million-euro ($9.5m) fine.

Judges in Catania in Sicily convicted the Tunisian man, Mohammed Ali Malek, on Tuesday of multiple manslaughter counts.

His Syrian crew mate, Mahmud Bikhit, was sentenced to five years in prison and fined nine million euros after being convicted of facilitating illegal immigration.

Prosecutors accused Malek of inadvertently ramming the overloaded fishing boat into the cargo ship that had come to its rescue on April 18, 2015, destabilising it.

The boat flipped after refugees rushed to one side.

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Both had claimed they were simple migrants and had been made to steer the boat by the real traffickers.

But survivors told investigators that Malek, who had lived in Italy in the past, was the captain.

They also said it was his lack of sailing skills that caused the deadly collision.

"I spent two years and six months in Italy and I have a young son with an Italian woman: I want to marry her and recognise the baby," Malek told the court in a plea before the verdict.

"It's the truth. I've always told the truth. Just as I immediately gave [police] my real name, and told them I was a passenger."

The boat was carrying people mainly from Gambia, Senegal and Mali, as well as Bangladesh, the Ivory Coast and Ethiopia.

Only 28 survived out of around 850 refugees on board.

Firefighters who recovered the mangled bodies from the rotting ship said they had been "packed in like on the trains for Auschwitz".

Young refugees trafficked in Italy

Source: News agencies