At least 10 North African migrants died when their rubber boat overturned in the southern Mediterranean while almost a thousand more from a total of seven vessels were rescued in a single day this week, Italian and Tunisian authorities said on Wednesday.
The Italian coast guard said in a statement that one of its ships in the area had rescued 121 people after their boat capsized on Tuesday some 50 miles north of Libya. Ten bodies were recovered.
Tunisian naval forces rescued all 81 migrants onboard another boat that had started taking on water off near the Tunisian island of Djerba on Tuesday night, the country's defence ministry said.
Several merchant ships assisted in migrant rescues from seven separate boats in a 24-hour period, bringing to safety almost 1,000 migrants, including 30 children and 50 women, one of them pregnant, the coast guard said.
They were identified as mostly Syrian, Palestinian, Tunisian, Libyan and sub-Saharan Africans, and they are being taken to Italian ports.
Last month, more than 300 people died in a one-week period trying to cross the sea from Libya to Italy, whose southern island of Lampedusa is just 300 kilometres (186 miles) from the Libyan capital of Tripoli.
The number of boat arrivals this year is already outpacing a record set in 2014, with 7,882 counted during the first two months of 2015, a 43 percent increase on the same period a year earlier, according to the Interior Ministry.
The U.N. refugee organisation UNHCR says at least 218,000 migrants crossed the Mediterranean by boat in 2014 and 3,500 lives were lost.
The surging numbers prompted Interior Minister Angelino Alfano to renew calls for the European Union to do more to help Italy handle the massive immigration flows.
The opposition anti-immigration Northern League party accused Rome and Brussels of "having blood on their hands" because rescue efforts encourage migrants to make the dangerous crossing, party leader Matteo Salvini said on Twitter.
Italy ended its large-scale search-and-rescue mission Mare Nostrum last year because of the cost and amid criticism that it encouraged people to attempt the journey.
Mare Nostrum was set up after more than 360 migrants drowned when their boat capsized near the Italian coast in October 2013.
It has been replaced by an EU border control mission, Triton, that does not have a specific search-and-rescue mandate and which has fewer ships and a much smaller area of operation hugging tightly to the Italian coast.
(By Steve Scherer; Additional reporting by Philip Pullella in Rome and Tarek Amara in Tunis; Editing by Catherine Evans and Raissa Kaso)