Canadian mining executive John Ridsdel dreamt of sailing his two yachts on the azure waters of the Philippines, his second home, until he was held hostage and later killed by a bandit group with ties to Islamic State jihadists.

On the eve of his abduction by the Abu Sayyaf in September last year, the 68-year-old blogged about the joys of sailing his multi-hulled catamaran, Aziza.

"Piloting this thing feels more like commanding an aircraft carrier than helming a sailboat," the semi-retired executive of TVI Mining wrote.

"You look out forward to an expanse of deck and the only thing that seems missing is the fighter jet. (“Sortie 42, cleared for takeoff”!)," he said.

Sailing the Aziza, Ridsdel said, was like "driving a house."

"It’s bright and airy, above the water, with lots of space to swing a cat (so to speak). Like a house. And then when you go sailing, you take the wheel and drive the house across the water," he said.

Ridsdel would sail the Aziza to the resort island of Samal, where the Abu Sayyaf would take him along with fellow Canadian Robert Hall, Norwegian resort manager Kjartan Sekkingstad and Filipina Marites Flor in the evening of September 21.

An emaciated Ridsdel pleaded for his life in at least two videos that the Abu Sayyaf posted on the internet. Filipino authorities said the group threatened to behead one of the four hostages if a P300 million ($6.4 million) ransom was not paid.

Canadian Prime Minister Justin Trudeau said Monday Ridsdel was killed in what he described as a "cold-blooded murder."

A severed head was found on Monday on Jolo island, the Abu Sayyaf's stronghold in the southwest, but the army could not immediately say if it was Ridsdel's.

Ridsdel was the second Abu Sayyaf captive to be executed in five months. In November, the bandits beheaded Malaysian Bernard to coincide with Malaysian Prime Minister Najib Razak's attendance in the Asia Pacific Economic Cooperation (APEC) leader's summit in Manila.

The Abu Sayyaf is a ragtag group of several hundred men founded in the 1990s with seed money from the Al-Qaeda, but more recently pledged allegiance to the Islamic State.

The group has gained international notoriety for kidnapping foreigners for millions of dollars in ransom. It has also claimed responsibility for the worst terrorist attacks in the Philippines, including the firebombing of a ferry off Manila Bay in 2004 that left over 100 people killed.