Refugees have fled Libya amid more than three months of fighting between Gaddafi loyalists and opponents [AFP]

The United Nations refugee agency says some 150 bodies have been recovered from the wreck of a ship that capsized off Tunisia carrying migrants fleeing the conflict in Libya.

The Geneva-based UNHCR said on Friday that at least 578 of the estimated 850 people on board survived the sinking on Wednesday.

"We know that many women and children are among the 150," Adrian Edwards, the UNHCR spokesman, said.

Edwards said that the survivors are being taken to refugee camps where they will receive counselling and assistance.

He says the incident "appears to be one of the worst and the deadliest incidents in the Mediterranean so far this year.''

The passengers are migrants from Africa and Asia who planned to enter Italy illegally, according to the Tunisian news agency.

Refugees have fled Libya amid more than three months of fighting between troops loyal to Muammar Gaddafi and opponents of his four-decade rule.

The conflict has prompted a Nato-led air assault against pro-government forces and has left thousands dead. The unrest in Libya erupted after revolts unseated the leaders of Egypt and Tunisia.

At least 16 people were confirmed dead among as many as 600 migrants heading to Italy who went missing when their ship sank soon after leaving the Libyan capital, Tripoli, last month, according to the United Nations.