The Philippines' Abu Sayyaf group has threatened to kill two German hostages unless Berlin pays ransom within 15 days, and stops supporting the US-led military campaign against the group that calls itself Islamic State.
The Islamist Abu Sayyaf group demanded 250m pesos ($5.6mn) for the Germans' release by October 11, and it publicly sided with the Islamic State in Iraq and Levant (ISIL), which was targeted this week in hundreds of air strikes by a coalition of Arab countries in the US-driven effort.
Large parts of Iraq and Syria have been taken over by the Islamic State group, which has proclaimed a "caliphate" in the region.
Abu Sayyaf called on Germany to "stop supporting America in the killing of our Muslim brothers in Iraq and the Levant in general, and the mujahidin of the Islamic State in particular", according to the US monitoring group SITE, which tracks the movement and communications of armed Islamist groups.
Germany has ruled out taking part in air strikes against ISIL. But, breaking a post-WWII policy of not exporting weapons into war zones and generally staying out of foreign military engagements, the government agreed to send weapons to Kurdish fighters and to send a squad of 40 paratroopers to train Kurdish fighters.
They are taking advantage of the international attention ISIS is getting so that the ransom would increase. All their activities are criminal in nature.
German doctor Stefan Okonek, 71, from Eltville near Frankfurt, and Henrike Diesen, 55, were abducted at gunpoint from their yacht while sailing in Palawan province, western Philippines, in April this year.
Abu Sayyaf reportedly pledged to "slaughter one of the two hostages" if its demands were not met. Philippine authorities said on Wednesday they were trying to verify the threat.
Senior Philippine military and intelligence officials said the German government and the hostages' family had been negotiating with the Abu Sayyaf faction holding the hostages. The family said they were not able to provide the group's initial ransom demand of $5.6mn, according to the officials.
The military chief in the western command that has jurisdiction over the southern island of Jolo, Lieutenant General Rustico Guerrero, on Thursday confirmed the hostages were being held by the Abu Sayyaf, but said the government would not be intimidated.
"They are taking advantage of the international attention ISIS is getting so that the ransom would increase. All their activities are criminal in nature," Guerrero told reporters.
Sawsan Chebli, a spokeswoman from the German foreign ministry, said the government was aware of the threat, adding Germany's efforts in regards to ISIL would not change.
"Threats are not an appropriate way to influence our policy towards Syria and Iraq," she told Al Jazeera.
Foreign ministry officials were continuing "efforts to release the Germans", Chebli said, declining to comment on a possible ransom payment. "We have an emergency task force that will extensively deal with the question how a release of the hostages can be achieved. But I cannot disclose details at this point."
Photos of the two hostages have circulated online for months. Abu Sayyaf released an image in August that showed the two hostages surrounded by masked fighters - one of whom held a machete near Okonek's head.
Another photo shows the hostages kneeling in front of a German flag, surrounded by men with machine guns.
Boosting its image
Zachary Abuza, a Southeast Asia politics and security analyst and author of the book Militant Islam in Southeast Asia, called Abu Sayyaf's announcement an "attempt to bolster their Islamist credentials".
Live Box 20146196311744332
"This gives them an opportunity to display their jihadist street creed," Abuza said. "At the very least, the threat of execution could lead to some or all of the $5.6 million ransom that they are seeking."
Based on past hostage-taking activities by Abu Sayyaf, military officials said the group will press ahead with their ransom demand, using the threat of beheading to prompt the family into agreeing to pay.
Philippine authorities said the two German hostages are believed to be held by an Abu Sayyaf faction led by the commander Hatib Hajan Sawadjaan in the mountainous town of Patikul, on the Jolo islands in Sulu province - considered an Abu Sayyaf stronghold. Abu Sayyaf is split into different factions and the group does not have a centralised leadership.
Abu Sayyaf group (ASG), which mainly operates in the predominantly Muslim southern Philippines, wants to establish an independent Islamic state in western Mindanao and the Sulu archipelago. According to Abuza, the group only has a few hundred members and is a network of gangs, with little coordination.
Abuza said Abu Sayyaf, long regarded as a bandit group, uses ISIL's prominence as leverage to get its demands met. He called the group's announcement to ally with ISIL "more of a publicity stunt".
"The ASG has always tried to link up their movement with the prevailing international jihadist movement. They see the air strikes as an opportunity to find common cause with their co-religionists, and to put their movement back in the limelight."
Abductions and beheadings
Abu Sayyaf is considered a "foreign terrorist" organisation by the US, and it has carried out kidnappings, beheadings and bombings.
In 2002, the US launched a six-month military campaign, supporting the Philippine military, to wipe out the group.
In 2001, its fighters beheaded American citizen Guillermo Sobero, who was abducted from an island resort in Palawan, the same province in which the two German hostages were kidnapped in April. The group had threatened to kill him unless the Philippine government called off its military operation against it.
Every time the government predicts the death of the ASG, it rebounds Sometimes it simply has a successful spate of kidnappings, which allow it to recruit and rearm.
Abu Sayyaf also claimed responsibility for a ferry bombing in Manila in 2004, in which 116 people were killed.
"Every time the government predicts the death of the ASG, it rebounds," Abuza said. "Sometimes it simply has a successful spate of kidnappings, which allow it to recruit and rearm."
This is not the first time that Abu Sayyaf has demanded ransom for kidnapped foreigners. In 2000, the group kidnapped 21 people from a Malaysian resort, 10 of whom were Westerners including the German family. They were released after having been held in the jungle on Jolo for three months.
Abuza said Abu Sayyaf has at least two other European hostages - a Dutch and a Swiss - as well as one Japanese and several Chinese citizens. Over the last decade, the group has mainly focused on kidnapping locals and demanding ransom for them, called a "board and lodging fee."
Although the US and UK have a strict no-ransom policy, other European nations, including Germany, reportedly have paid money to free their citizens from armed groups in the past.
A 27-year-old German man, who was kidnapped in June 2013 by ISIL fighters while on a humanitarian aid mission in Syria, was released in June this year, German security officials said. The government paid a "substantial" ransom for his release, according to the German newspaper Die Welt am Sonntag.
The German foreign ministry, however, denied having paid a ransom "in any form".
Jason Gutierrez contributed to this report from the Philippines