(CNN)A picture and audio posted online Saturday purport to show that one of two Japanese hostages held by ISIS has been killed after a deadline for ransom passed. It also appears to relay the group's new demand for the other's freedom: a prisoner exchange. The static image, shown in a video file posted by a known ISIS supporter, shows surviving Japanese hostage Kenji Goto, alone, in handcuffs and dressed in orange, holding a photo of what appears to be beheaded compatriot Haruna Yukawa. Japanese Prime Minister Shinzo Abe said Sunday that the video is "highly credible." U.S. authorities said they had no reason to doubt its authenticity.
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Japanese and U.S. authorities say the video seems authentic
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Hostage Kenji Goto holds a photo of what appears to be beheaded compatriot Haruna Yukawa
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ISIS is now demanding the release of a prisoner in Jordan in exchange for Goto
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U.S.
"@placeholder has known this pain and horror ourselves, and we stand with Japan not just in sadness, but in solidarity and strength," he said in a statement.
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"America has known this pain and horror ourselves, and we stand with @placeholder not just in sadness, but in solidarity and strength," he said in a statement.
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Japanese
@placeholder officials had said they would not yield to threats, but they would do everything they could to secure the hostages' safe release.
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ISIS
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The government was trying to confirm if that e-mail came from @placeholder, the reports said.
Haruna Yukawa
Haruna Yukawa
The aims and activities of @placeholder, a 42-year-old unemployed widower, are murkier.