Around 75 migrants are lost at sea according to survivors of a shipwreck off Italy who were plucked to safety by the navy, the UN's refugee agency said on Wednesday.
A group of 27 people rescued on Tuesday "said that there were another 75 people on board the boat they were travelling on, who are therefore believed lost at sea," the agency said in a statement.
Accounts of the shipwreck were gathered by UN workers in Sicily who spoke to survivors recovered by Italy's "Mare Nostrum" ("Our Sea") rescue operation.
"According to the information gathered so far, the shipwreck occurred because the rubber dinghy they were travelling on was in a poor state and was overcrowded," Catania prosecutor Giovanni Salvi was quoted as saying by Italian media.
Salvi has opened an investigation into the shipwreck, news of which came just three days after the bodies of 45 migrants were discovered in the hold of an overcrowded fishing boat, where they appeared to have suffocated to death.
The number of migrant arrivals has now soared past the record 63,000 set in 2011 during the Arab Spring uprisings, and EU border agency Frontex has warned that calm seas across the summer will encourage many more to attempt the trip.