Philippine police and military officials say they are pressing on with a manhunt for about 30 Muslim militants after three were convicted of the 2011 kidnappings of an American woman, her teenage son and a Filipino relative vacationing in the country's south.

A Philippine regional trial court convicted the three Abu Sayyaf militants last week and sentenced them to life in prison for the July 12, 2011, kidnappings of Gerfa Lunsmann, her American son Kevin and her Filipino relative Romnick Jakaria from an island beach cottage off Zamboanga city.

Military and police officials welcomed the convictions Monday and said they were searching for the remaining suspects, including notorious Abu Sayyaf commander Puruji Indama, who has also been linked to bomb attacks and other terrorist acts.