Manila, Sep 18 (IANS): A Norwegian man held captive for almost a year by a militant Islamist group in the Philippines has been freed Saturday, according to authorities.

Abu Sayyaf released Kjartan Sekkingstad on Saturday evening, Western Mindanao Command spokesman Major Filemon Tan. said.

Sekkingstad's release was an offshoot of ongoing military operations against the Abu Sayyaf group, Tan told CNN Philippines.

The Moro National Liberation Front, which is in peace talks with the government, assisted authorities in the operation, he said.

It was unclear whether a ransom was paid to secure Sekkingstad's release.

Sekkingstad was abducted from a resort on Samal island, which lies off the coast of Mindanao, on September 21, 2015.

Three people were kidnapped with him: Canadians John Ridsdel and Robert Hall, and Filipina Tess Flor.

Hall, Ridsdel and Flor were visiting the resort's marina on their yacht and Sekkingstad was the manager of the property.

Abu Sayyaf initially demanded a $6.3 million ransom for each of the victims to be paid by April 25, according to Philippine state media.

In March a jarring video surfaced, showing the four pleading for their lives.

In April, after murdering Canadian hostage Ridsdel, the group reset the deadline to June 13 for the remaining three hostages.

A video obtained in May by SITE, a group that monitors extremist and terrorist groups, showed three hostages surrounded by six armed militants.

Abu Sayyaf beheaded Hall in June.

Flor was released June 24, less than a week before Rodrigo Duterte officially assumed the presidency. He presented Flor to the public during a police turnover ceremony in Davao.

CNN Philippines reported that Sekkingstad spoke by telephone with Presidential Peace Adviser Jesus Dureza after his release and in his first words thanked Duterte.

Dureza said he would present Sekkingstad to Duterte Sunday.