ZAMBOANGA CITY, Philippines - A mother and son, both US citizens, and a Filipino relative, who were on brief vacation, were abducted by heavily armed gunmen in an island off the coast east of this city at pre-dawn Tuesday, police and civilian officials said.

The victims were identified as Gerfayeatths Lunsmann, 50, her 14-year old son Kevin Erick Lunsmann, both US immigrants; and her nephew Romnick Jakaria, 19, a native of Malamawi Island, Basilan province.

The two immigrants were on vacation in Tictabon Island when they were abducted from their newly built rest house about 3 a.m Tuesday, according to the island village chairman Hadji Atang Mohammad Nur, who reported the incident to police authorities.

The village official identified the two immigrants through their passports, who were staying in the area since they arrived for their vacation.

Nur told a local radio that the woman left the country since 9 years old after she was adopted.

The victim's nephew arrived in Tictabon Island Monday and had an overnight stay before they were abducted.

City Police office director Senior Supt. Edwin de Ocampo confirmed the abduction incident and said a pursuit and search operation has been on going to track down the location of the kidnappers.

About 14 fully armed gunmen on board two motorized pumpboats swooped down the victims' rest house and cornered all the unarmed bodyguards of the victims, said Chief Inspector Nonito Asday, commander of the Sacol Island police station.

Search around the island yielded negative result, Asday said, adding there was information that the suspects sped towards the direction of Basilan, a known bailiwick of the notorious Abu Sayyaf group.