MANILA, Philippines — Suspected al-Qaida-linked gunmen have abducted two Filipino sisters who traveled to a dangerous mountainous area in the southern Philippines to work on a film about Muslim farmers, police and military officials said Sunday.

Nadjoua and Linda Bansil were taken by about 10 gunmen Saturday in Sulu province's Patikul town where they filmed coffee farmers. At least three companions of the sisters, who were in a van, fled on a motorcycle or were left behind by the gunmen, Patikul police chief Senior Inspector Christopher Gutierrez said.

Police were trying to locate the gunmen and their victims, Gutierrez said.

"We're trying to track down the abductors and the victims and possibly launch a rescue operation with the help of the military," Gutierrez said by telephone.

Marine Col. Jose Cenabre said the gunmen belong to the Abu Sayyaf, a group notorious for ransom kidnappings, beheadings and other atrocities, but Gutierrez said police were still checking if the abductors were from an allied group of young gunmen behind several kidnappings.

Gutierrez said the women, who were guests of a Sulu-based sultan, did not coordinate with police before their trip to the dangerous Patikul hinterlands. They reportedly visited Mount Sinumaan, a rugged mountainous area where the Abu Sayyaf maintains a camp, and were on their way back to the provincial capital of Jolo when they were stopped by the gunmen.

The sisters were born in Algeria from an Algerian mother and a Filipino father but grew up in the Philippines, where they have been involved in recent years in producing independent films. One of their works, a short film about the travails of impoverished Filipino sea gypsies, has won praise, according to a close relative who spoke on condition of anonymity for security reasons.

Abu Sayyaf militants have been holding a number of hostages in the jungles of Sulu, including two European bird watchers and a Jordanian journalist who were kidnapped last year. The militants are active in Sulu, a predominantly Muslim province about 950 kilometers (590 miles) south of Manila, where they have survived in their jungle encampments despite years of U.S.-backed Philippine offensives.

Veteran Jordanian TV journalist Baker Atyani and his two Filipino crewmen were kidnapped last June by Abu Sayyaf militants whom they had sought to interview in Patikul's jungles. His two Filipino companions were freed in February but Atyani, who gained prominence for interviewing Osama bin Laden in Afghanistan a few months before the Sept. 11, 2001, attacks, remains in captivity, police say.

Bird watchers Ewold Horn of the Netherlands and Lorenzo Vinciguerra of Switzerland are also believed to be held in Patikul by the Abu Sayyaf, police say.

Meanwhile, about six gunmen seized teacher Alrasid Rojas in a predominantly Muslim coastal village in southern Zamboanga city late Saturday and took him away by speedboat. Government forces launched a search in nearby areas, including Basilan island, where Abu Sayyaf gunmen have a presence, police said Sunday.

Officials said it was unclear whether the abduction was carried out by the Abu Sayyaf, kidnap gangs or others.