Eleven bodies have been recovered by Tunisia's coastguard after a boat carrying Tunisian ​migrants sank at the weekend en route to Italy, with three ‌others still unaccounted for, the National Guard said on Sunday.

Coastguard, military, and civil protection teams, backed by two helicopters, continued searching for the missing.

The boat, which ​set off early on Thursday with 15 mostly young people ​on board, sank off the Tunisian coast, and so far ⁠only one person was rescued alive, the head of a migrant rights ​group said on Saturday.

The man who survived said he had been adrift ​at sea for 48 hours before being rescued by a commercial vessel.

Among those on board were seven members of the same family and a man with his ​pregnant wife, the head of the Tunisian Observatory for Human Rights told ​Reuters.

All of the migrants were from the Ben Guerdane area in southeastern Tunisia, and ‌dozens ⁠of young people gathered late on Saturday in the town near the Libyan border to demand that search operations be accelerated.

Police fired teargas to disperse the protesters.

The central Mediterranean route from the North African coast is ​one of the ​world's deadliest migration ⁠routes, used by migrants from Africa and the Middle East seeking to reach Europe, often in overcrowded or ​unseaworthy boats.

Human Rights Watch, Amnesty International and dozens of ​other ⁠human rights and humanitarian groups said in a statement last month that a migration agreement between Tunisia and the European Union had fuelled and normalised serious ⁠abuses ​against migrants and asylum seekers in Tunisia.

The ​groups called on the EU to suspend funding for migration and border-control activities involving Tunisian security ​forces.