Almost 3,600 migrants have reportedly been rescued from overcrowded boats sailing from Africa to Europe over the past 48 hours, with sea conditions seen as perfect for attempting the crossing.

While more than 600 migrants were brought ashore at the port of Catania in Sicily on Thursday, rescuers picked another 2,500 from boats off the coast of Libya, Italy's coastguard said.

Most of those who arrived in Catania had been picked up by the British warship HMS Bulwark and were Somali and Nigerian, Catania port officials said.

With Libya engulfed in strife, people smugglers are increasingly free to pack migrants onto unsafe boats, and they are expected to push total arrivals in Italy for 2015 to 200,000, an increase of 30,000 over last year, according to an Italian interior ministry projection.

Sandra Dike, a heavily pregnant 20-year-old Nigerian woman, said she left her home country because of the danger of attacks by the Boko Haram.

"It's not safe to go to a public place, like a church, the market. They [Boko Haram] might bomb the place at any time," she said.

"The war in Libya is worse. That's why we decided to come to Italy."

Boko Haram, which has killed thousands in its attempt to carve out a state, has suffered major setbacks this year following a co-ordinated military offensive by Nigeria, Niger, Chad and Cameroon.

A German ship, Italian navy vessels, a merchant ship and Italy's finance police and coast guard all conducted rescue operations on Thursday, a coast guard official told Reuters.

Surge in rescues



The 40-metre Phoenix, based in Malta and run by the Migrant Offshore Aid Station (MOAS) and Doctors Without Borders, rescued 561 people, including 136 women and 60 children, mostly from Eritrea.

The ship picked up 188 people on Wednesday.

The surge in rescues comes just a day after the EU announced a plan to distribute asylum-seekers more fairly around its member states and take in 20,000 more refugees.

At the beginning of the month when the weather also was favourable, about 6,800 people were rescued over three days, while dozens were said to have drowned.

With the estimated number of migrant deaths at sea this year approaching 2,000, and after as many as 800 died in a single shipwreck last month, the EU has bolstered its Triton sea mission to help Italy conduct the rescues.