Another eight were injured and taken to hospital, including two who swallowed a considerable amount of seawater and fuel.

Armed Forces of Malta deputy commander Colonel Edric Zahra told reporters that the incident happened at about midday when the eight-metre (26-ft) boat was four miles (6.5 km) south of Malta.

Some 21 migrants were rescued and taken to a migrant centre. They are believed to be from Syria, Eritrea, Ethiopia and Egypt.

Mediterranean sea crossings from North Africa to Italy or Malta are among the most dangerous migration routes in the world. Last year almost 2,500 migrants died or went missing on those routes, the International Organization for Migration says.

The vast majority of migrants head for Italy. Malta's armed forces rescued 380 migrants at sea last year, Home Affairs Minister Byron Camilleri said in parliament in January.

(Reporting by Christopher Scicluna; Editing by Nick Macfie)