The video, identified as being made by the Islamic State group’s al-Furqan media arm and posted on militant websites associated with the extremist group, mirrors other hostage threats it has made.
It appears to show a militant, flanked by two hostages in orange jumpsuits who are identified as Kenji Goto Jogo and Haruna Yukawa.
The Islamic State militant threatens to kill the two hostages unless a $200m (£130m) ransom is paid. The video has not been independently verified.
Japanese Prime Minister Shinzo Abe said Islamic State’s threat against the two purported captives was “unacceptable”.
“Extremism and Islam are completely different things,” Abe said. “We strongly demand the immediate release of the Japanese citizens unharmed … The international community needs to respond firmly and cooperate without caving into terrorism.”
Hundreds of victims
The militant resembles and sounds like “Jihadi John” – a British militant involved in filmed beheadings by the Islamic State group.
The United States is fully supportive of Japan in this matter. We stand in solidarity with Japan and are coordinating closelyU.S. State Department Jen Psaki
Japan’s Foreign Ministry’s anti-terrorism section has seen the video and analysts are assessing it, a ministry official said.
The official spoke on condition of anonymity because of department rules.
In August, a Japanese citizen believed to be Yukawa, a private military company operator in his early 40s, was kidnapped in Syria. His reason for going to Syria remains unclear. Goto is a Japanese freelance journalist who went to report on Syria’s civil war last year.
Militants from Islamic State have beheaded and shot dead hundreds of captives – mainly Syrian and Iraqi soldiers – during the group’s sweep across the two countries, and has celebrated its mass killings in extremely graphic videos.