Japanese prime minister Shinzo Abe has expressed anger early at a video purporting to show the killing of a Japanese citizen by Islamic State militants, and insisted Tokyo will not bow to terrorism.
He reiterated the government's view that the video, which appeared to show an executed Haruna Yukawa with the voice of captive Kenji Goto, was "an outrageous and unacceptable act of violence".
“I have a strong sense of anger,“ Abe told reporters in brief remarks after an emergency cabinet meeting to discuss the crisis. “We will not give in to terrorism.”
Demanding the immediate release of journalist Mr Goto unharmed, Mr Abe said Japan will work with other countries to secure his release. He did not take questions from reporters.
The authenticity of the video has not been verified.
It purports to show hostage Kenji Goto Jogo saying his fellow captive Haruna Yukawa has been beheaded by their Islamic State captors.
According to the video, IS has dropped its demand for a $200 million US dollar ransom from the Japanese government and wants the release of female suicide bomber instead. The report is as yet unconfirmed.
Japan's NHK said the Tokyo government is trying to verify the video. Chief cabinet secretary Yoshihide Suga said that cabinet ministers were holding an emergency meeting about the new message, the release of which he condemned as unforgivable.
The SITE Intelligence Group, which monitors jihadist websites, said Islamic State-linked Twitter accounts distributed a video in which Mr Goto (47) stated that his fellow captive had been executed.
The three-minute video features a still image of Goto holding a picture of a beheaded Mr Yukawa (42).
Speaking in English, he blames Japanese prime minister Shinzo Abe for Mr Yukawa's death. He says IS is now demanding the release of Sajida al-Rishawi, a female suicide bomber dispatched by al-Qaeda in Iraq to attack a hotel in Jordan in 2005.
“It is simple. You give them Sajida and I will be released,” he says. “At the moment, it actually looks possible and our government are indeed a stone throw away. How? Our government representatives are ironically in Jordan, where their sister Sajida is held prisoner by the Jordanian regime.”
The kidnpappers had given Mr Abe 72 hours to pay a $200 million ransom to secure the release of Mr Goto, a journalist, and Mr Yukawa, an adventurer fascinated by war. The deadline expired on Friday.
Japan promised not to give up “until the very end” on efforts to rescue the two men.
Worshippers at Tokyo's largest mosque on Friday offered prayers for the two hostages. "All Muslims in Japan, we want the Japanese hostages to be saved as soon as possible," said Sandar Basara, a worker from Turkey.
Mr Goto's mother made an appeal for his rescue. "Time is running out. Please, Japanese government, save my son's life," said Junko Ishido. "My son is not an enemy of the Islamic State."
She said she was astonished and angered to learn from her daughter-in-law that Mr Goto had left for Syria less than two weeks after his child was born in October to try to rescue Mr Yukawa.
Japan has joined other major industrial nations in the Group of Seven in opposing ransom payments. US and British officials said they advised against paying.
Meanwhile, the United States and its coalition partners have launched another round of air strikes against Islamic State militants in Iraq and Syria, conducting 26 strikes since early Friday.
In a statement on Saturday from the Combined Joint Task Force leading the military operation, officials said 13 strikes hit in Syria and also 13 hit in Iraq. In Syria, 12 air strikes targeted Islamic State positions near Kobani.
In Iraq, five strikes hit near Mosul and five near Tal Afar, the statement said.
Agencies