THE Canadian government has “every reason to believe” that one of its citizens kidnapped by Islamic militants in the southern Philippines nearly nine months ago has been killed, Prime Minister Justin Trudeau said on Monday.

Members of the notorious kidnap-for-ransom Abu Sayyaf gang had said they would murder Robert Hall if they did not receive 300 million pesos ($8.8 million) ransom by Monday.

Hall was among four people abducted in September last year from aboard yachts at a tourist resort on Samal island in the southern Philippines. He would be the second Canadian from the group to be killed.

“It is with deep sadness that I have reason to believe that a Canadian citizen, Robert Hall, held hostage in the Philippines since September 21, 2015, has been killed by his captors,” Trudeau said in a nationally televised address.

“We continue to work closely with the authorities in the Philippines to formally confirm Mr Hall’s death. We have every reason to believe that the reports are unfortunately true,” Trudeau said.

The Canadian flag atop parliament was lowered to half-mast in Hall’s honour. “The vicious and brutal actions of the hostage-takers have led to a needless death. Canada holds the terrorist group who took him hostage fully responsible for this cold-blooded and senseless murder,” Trudeau said.

After Trudeau’s comments, Philippine authorities said late on Monday they recovered a human head on the Abu Sayyaf stronghold of Jolo island.

“Yes we recovered a caucasian-looking one ... Seems like Robert Hall,” regional military spokesman Major Filemon Tan told AFP, adding police investigators were now trying to establish the person’s identity.

Listed by the United States as a terrorist organisation, the Abu Sayyaf is a loose network of Islamic militants that was founded in the early 1990s with money from Osama bin Laden’s Al-Qaeda network.