MANILA — Philippine Islamic militants have released a video showing an elderly German sailor abducted at sea late last year is alive, according to a security group that monitors jihadist activity.

The Abu Sayyaf released the video of Jurgen Kantner on Wednesday along with photos that had a date stamp of December 26 last year, SITE Intelligence Group reported.

The military on November 7 last year reported finding Kantner's yacht, Rockall, adrift off the southern Philippines.

The body of a woman with a bullet wound, later identified by the hostage as his partner, Sabine Merz, was found on board the vessel.

In Berlin, German authorities declined to comment on the video.

"As a matter of policy, the government does not comment on cases of kidnapping and hostage taking of German citizens abroad," said a source from the German foreign ministry.

The Abu Sayyaf, which has pledged allegiance to the Islamic State group, later claimed the abduction and the killing.

The group is made up of several small armed bands based in the mainly Muslim southern islands of Basilan and Jolo, where they are also holding a Dutchman and foreign crew members of several other vessels.

It is blamed for the Philippines' deadliest bombing attacks as well as dozens of kidnappings-for-ransom. The Abu Sayyaf murdered two Canadian hostages last year after ransom demands were not met.