Abu Sayyaf group set the deadline of October 10 to meet the demands including a ransom of USD 5.6 million (250 million pesos) in a letter sent to the families of the two hostages, the German and Filipino government in lieu of the safe release of the Germans who were kidnapped during a yachting holiday off the Palawan Island in April.
The threat came just a few days after IS asked its supporters to kill Westerners whose nations have joined the US-led global coalition of more than 50 nations to fight the militant group which has gained control over a large part of Syria and Iraq, and proclaimed a Caliphate.
In Algeria, Jund al-Khilifa, a jihadist group linked to IS yesterday claimed to have beheaded a Frenchman, Herve Gourdel, 55, in a video posted online after France rejected its demand to halt strikes in Iraq. He was abducted last Sunday.
Germany's foreign ministry in Berlin has said a crisis management team is working on various possibilities to secure the safe release of the hostages.
Founded in the early 1990s and listed as a terrorist organisation since 1997, Southern Philippines-based Abu Sayyaf group started kidnapping foreigners in the early 2000s.