Japan said it was verifying a video that claims Japanese hostage Haruna Yukawa, held by Islamic State (IS) militants, has been killed.
IS on January 20 threatened to kill Yukawa and another Japanese hostage, Kenji Goto, unless Japan paid a $200-million ransom within 72 hours.
Japanese Prime Minister Shinzo Abe, who arrived at his office in Tokyo after midnight on January 25, condemned the latest video as "an outrageous and unacceptable act of violence."
The video purports to show Goto holding a picture of what appears to be the body of Yukawa. It also says the group will release Goto only in exchange for the release of Al-Qaeda-linked attempted female suicide bomber Sajida Rishwai, an Iraqi held in Jordan.
Japanese cabinet ministers are holding an emergency meeting about the video.