Canada's prime minister has condemned the "cold-blooded murder" of a Canadian - held hostage for months - by Islamist militants in the Philippines.
John Ridsdel, 68, was captured alongside Canadian Robert Hall, a Norwegian man and a Filipino woman last September.
At the time, Mr Ridsdel was taken Abu Sayyaf militants from a marina on southern Samal Island.
On Monday a severed head was found on a remote Philippine island.
The militants had threatened to kill one of the three male hostages if a large ransom was not paid by 3pm Monday local time (0800 GMT).
Canada's premier Justin Trudeau confirmed the death and said both the Canadian and Philippines governments would pursue those responsible for the "heinous act".
Philippine forces were moving to rescue the abductees as the Abu Sayyaf's deadline for the ransom payment lapsed, the military said.
The militants reportedly demanded 300 million pesos (£4.5m) for each of the foreigners - a reduction from their earlier demands.