Prime Minister Shinzo Abe looked dismayed during a press conference on Sunday, as he told reporters that a video depicting the execution of Japanese hostage Haruna Yukawa is very likely to be authentic.

Viewers had been hoping that the clip, posted by the Islamic State group on Saturday, was a fake. But a Japan Times article said the clip features a gruesome still image of Yukawa’s corpse, before quoting Abe as saying the “credibility” of the footage was “high.”

According to Reuters Abe went on to demand that the radicals release their second hostage, freelance reporter Kenji Goto.

The Prime Minister went on to say, “Such an act of terrorism is outrageous and impermissible, which causes me nothing but strong indignation. Again, I strongly demand that Mr. Kenji Goto not be harmed and be immediately released.”

The latest video also featured a plea from Goto, who said he would be released in exchange for an Iraqi woman held in Jordan. This marks a sharp shift in the captors’ demands, who had initially pushed for a $200 million ransom under a 72-hour deadline last week—an amount equal to Japan’s aid funding in the region.

According to the Japanese Kyodo news agency, Goto’s mother said that she doubts that her son would push for such a prison exchange, before telling public broadcaster NHK that the entire situation is “unbearable.” She added: “What I want to tell the Islamic State is that Kenji’s ideal is world peace.”

Apparently Goto extended much of that goodwill to his fellow captor. NHK, among other outlets, have reported that Kenji Goto was captured himself after attempting to secure Yukawa’s release, after he launched a security firm in Syria.

Yukawa’s father, Shoichi, told NHK that Goto’s sacrifice only compounds his grief, adding: “I am filled with disappointment, that it has finally come to this. I feel pained, that he (Goto) risked his life out of concern (for my son) and ended up being captured. I hope he can be released as soon as possible, and return to Japan to continue his activities.”

Goto’s fellow reporters shared that sentiment during a 200-strong rally in front of the Prime Minister’s official residence on Sunday, according to Japan Today. Many of the demonstrators hosted signs that read “I am Kenji,” a statement which has become a viral online hashtag as numerous netizens show their support for the detained reporter.

—Kyle Mullin

Image of Junko Ishido, mother of journalist Kenji Goto, at a press conference held at the Foreign Correspondents’ Club of Japan: AFP