Testimony from survivors brought to Italy suggests that more than 120 refugees drowned while trying to reach Europe.

At least 126 refugees are feared to have drowned in the Mediterranean Sea after the motor of their boat was stolen, causing it to sink, the United Nations’ migration agency has said.

According to testimony from four survivors brought to Italy, the refugees – mainly Sudanese – left on Thursday from Libya trying to make the dangerous crossing to Europe, Flavio Di Giacomo, spokesman for the International Organization for Migration (IOM) said on Monday.

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The men said that after a few hours at sea a group of Libyan traffickers intercepted their boat, he added.

“They stole the motor – something which has happened a few times recently – and at that point, the boat started to take on water and sank.”

Rescued by fishermen

Passing Libyan fishermen rescued the four survivors – two Sudanese and two Nigerian men, and put them on another boat with about 1,000 other refugees. They were eventually rescued and brought to the Sicilian port of Palermo.

“They were in shock, traumatised by what had happened, and exhausted,” Di Giacomo said, adding that there were no official witnesses to what had happened, but refugees from the second boat had confirmed the account.

Gangs in Libya have built a lucrative trade out of packing refugees into rickety boats heading for Italy, where more than 65,000 have arrived so far this year.

As of June 14, 1,828 people are believed to have died trying to reach Europe, according to IOM figures.

READ MORE: UN urges Libya to release all refugees, asylum seekers

Debate over dealing with the refugee influx is becoming increasingly bitter in Italy, whose economy is lagging behind its European peers ahead of national elections next year.

Most of the people attempting the perilous journey originally come from Nigeria, followed by Bangladesh and other sub-Saharan countries.