The Philippine government today condemned the "barbaric" killing of a German hostage by Islamist militants who released a video purportedly showing the execution.
"We grieve as we strongly condemn the barbaric beheading of yet another kidnap victim," presidential peace adviser Jesus Dureza said in a statement following the release of the video on various websites and chat groups.
"Up to the last moment, many sectors, including the armed forces of the Philippines exhausted all efforts to save his life," he added. "We all tried our best. But to no avail."
In the one-minute-34-second video, the 70-year-old captive wore sandals, grey pants and a black T-shirt and slumped on a grassy lot while a man held a sickle to his neck.
"Now he'll kill me," the German man said.
His captors shouted "Allahu Akbar" after the beheading, which was carried out on Sunday after a ransom demand deadline had passed.
The Abu Sayyaf group demanded 30 million pesos (US$600,000) be paid by Sunday afternoon or they would behead the captive.
Dureza urged the public to support the government's fight against terrorism.
"Terrorism has no place in a country like ours and we as a people must confront violent extremism every time it rears its ugly head," he said. "There must be a stop to this killing of the innocent and the helpless."
Germany's security authorities are examining the video to assess its authenticity, Foreign Ministry spokesperson Martin Schaefer said today.
It was impossible to say whether the video was authentic "because of the shortness of the time-frame," he said.
Schaefer called the images "harrowing".
He refused to comment on the details of the case, such as whether a ransom had been demanded, stressing that official statements did not contribute to the resolution of abduction cases.
The video "is not enough" proof that the execution took place, said brigadier general Restituto Padilla, a spokesperson for the Philippine military.
When asked if he has seen the video, he replied: "No, I have not and I will not dignify the video by watching it."
The German man had been seized by militants on Nov 5 from his yacht in the southern Philippines. They shot dead the man's 59-year-old wife after she fought back. Her body was left in the boat.
Colonel Edgard Arevalo, another spokesperson for the military, said the troops were making every effort to find the body of the German man.
"We have sought the help of local governments and the Moro National Liberation Front (MNLF) in looking for the body of the latest victim of the Abu Sayyaf," he said.
"Until we find the body of the victim, we still hold on to the hope (that he is still alive) and we will continue to conduct combat operations," he added.
The MNLF is a rebel group that signed a peace agreement with the government in 1996 and is based on the island of Jolo, 1,000km south of Manila.
According to intelligence reports, the beheading of the German national took place in a village in the town of Indanan on Jolo.
Last year, Abu Sayyaf beheaded two Canadian nationals after they did not receive ransom for the two hostages. The Canadians were abducted in September 2015 with a Norwegian man and a Filipino woman, who were later both freed separately.
There is no confirmation of that Norway made a ransom payment for their hostage's release. The Philippine government has a no-ransom policy and discourages payments by other parties, but has not been able to stop such payoffs in past instances.
The Abu Sayyaf militants are believed to be holding captive more than 20 other hostages in the southern Philippines.
Aside from undertaking kidnappings for ransom, the Abu Sayyaf group has been blamed for some of the worst terrorist attacks in the Philippines.
President Rodrigo Duterte has directed the military to crush the militant group and warned that it could be a source of recruitment for the Islamic State extremist militia.