Islamist militants in the southern Philippines have released a video purportedly showing three hostages pleading for help. A masked militant has vowed to execute them if the group's demands are not met.

"I'm a hostage at Sulu Island. I'm appealing to the Canadian government, the Philippine government, friends, family, anybody who can possibly help us. If the demand is not met, we will be executed like our friend John a few days ago," said Kjartan Sekkingstad, hostage by Abu Sayyaf Group.

"To the Philippine government: Please stop shooting at us and trying to kill us. These guys are going to do a good job of that," said Robert Hall, hostage by Abu Sayyaf Group.

The group released 10 Indonesian hostages on Sunday, ending a month-long ordeal during which a kidnapped Canadian was executed after a ransom deadline passed. Abu Sayyaf, a brutal militia known for amassing tens of millions of dollars from the ransom business, is now holding 13 other people. A Philippines armed forces spokesman says efforts to rescue three hostages are ongoing. 

"And your Armed Forces will continue to work to secure the safety of the hostages who still remain in the hands of these bandits. We have not stopped. We have not let up on ongoing operations and we will not cease on doing this until we are able to make these personalities, or these bandits and criminals, accountable for their actions," said Brigadier General Restituto Padilla, spokesperson of Armed Forces for Philippines.