Italian authorities are lowering by as many as 200 to 300 people the estimated number of migrants who died in a 2015 shipwreck that spurred Europe to beef up its Mediterranean rescue efforts.

Survivors of the April 18, 2015, wreck had told investigators the boat was carrying as many as 700-800 people, most of them trapped in the hull. Only 28 survived.

But after the ship was raised from the seabed this week and officials got a look at its dimensions, they revised the estimated number of original passengers.

Divers originally recovered 169 bodies and discovered another 10-11 once the resurfacing operation got under way.

As a result, Navy Rear Admiral Pietro Covino told a press conference Thursday there were likely "no fewer than 300" bodies left in the hull.