A boat filled with about 120 illegal immigrants capsized off Libya's Zuwara coast, Ayoub Qassim - the spokesman of the Libyan Navy - has reported.

Qassim told the press on Thursday that the boat left Libya's shores on last Friday, while the wreckage was found on Wednesday by Zuwara coastguards.

"It was found in Sidi Sayeed area, 20 km away from Zuwara," added Qassim.

He said that seven migrants were found alive, while four other bodies were recovered, adding that the survivors were in serious conditions as they stayed in the water for three days.

"One of the survivors dies after we sent them to hospital. The other six are under treatment and they are now in good conditions." Qassim indicated.

"Some of the migrants jumped from the boat before the waves had broken it to pieces and washed it ashore." Survivors confirmed.

Zuwara security personnel and residents both rushed to the scene of the shipwreck and managed to rescue 30 migrants, most of whom are being treated in Zuwara hospital.

"90 are missing, and five have drowned in this incident." Qassim explained.