A manhunt is underway in the Philippines after four tourists were kidnapped Monday by a group of 11 men from the Holiday Oceanview Samal resort on Samal Island, a military spokesman said Tuesday.

Military spokesman Col. Restituto Padilla told The Philippine Daily Inquirer that surveillance video shows the 11 armed men taking two Canadians, a Norwegian and a Filipino and fleeing on a boat about 11:30 pm Monday. Two Japanese tourists made an unsuccessful attempt at trying to intervene, but weren't harmed or abducted.

Capt. Alberto Caber revealed the identities of the victims as Robert Hall and John Ridsel, of Canada, and Kjartan Sekkingstad, of Norway, reported the New York Times. The fourth victim, a Filipino woman, has not been identified, he noted.

It's unknown who's responsible for the kidnapping, but authorities believe the perpetrators may be Abu Sayyaf, a Muslim militant group who often engage in kidnappings of locals and foreigners in often successful efforts to extort ransoms, according to the AFP.

In their most recent kidnapping of foreigners, the group abducted a German couple in April last year. The couple was released six months later after the group received the $5.4 million it had demanded in ransom.

Padilla noted that the authorities are doing everything they can to rescue the hostages.

"We can assure the public that the joint forces of the government, led by the police, air assets of the air force and naval assets are all working hand in hand to free the captives," he said.

The kidnappers have yet to make a statement on how much money they want for the hostages safe return.