TUNIS - Tunisia's coastguard has recovered the bodies of nine migrants while six others are still missing after their boat sank off the Tunisian coast, a judicial official said on Thursday, in the latest migrant boat disaster in the Mediterranean.

The coastguard has so far rescued 27 people who were on the boat when it broke down and took on water due to bad weather. According to survivors' testimonies, the boat had been carrying at least 42 people when it sank.

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Judge Farid Ben Jha told Reuters that a search was underway for at least six migrants who had been on the boat when it sank off the coast of Chebba.

All the migrants on the boat were from sub-Saharan African countries.

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Tunisia is grappling with an unprecedented migration crisis and has replaced Libya as the major departure point for both Tunisians and people from elsewhere in Africa seeking a better life in Europe.