Reactions to the purported decapitation of Kenji Goto, a Japanese journalist who was kidnapped by "Islamic State" militants in October, poured in from world leaders on Sunday.
Calling it a "heinous murder," US President Barack Obama expressed a sentiment conveyed also by UK Prime Minister David Cameron and French President Francois Hollande, whose countries have each lost citizens to IS in killings recorded on camera.
"Through his reporting, Mr. Goto courageously sought to convey the plight of the Syrian people to the outside world."
Prime Minister Cameron further pointed to the meaning of yet another IS beheading video only served to illustrate, by way of example, "the violence that so many have been subjected to in Iraq and Syria."
UN Secretary General Ban Ki-moon also condemned the killing, calling it "barbaric."
Late on Saturday, a video circulated online which purported to show the beheading of Goto by a masked man. The footage was very similar to previous IS execution videos and, according to Japan's defense minister, is "highly likely to be authentic." The video still awaits independent verification.
The mother of the high-profile journalist spoke to reporters on Sunday as well.
"Facing such a tragic death, I'm just speechless," she said.
Her son had been abducted in Syria while he was attempted to win the release of his compatriot, Hauna Yukawa. IS beheaded Yukawa one week ago.
Yukawa's father also expressed his heartbreak and speechlessness after hearing the news.
Goto travelled to Syria "[to save my son] only to suffer the worst possible outcome."
"People killing other people - it's so deplorable. How can this be happening?"
Last week, IS demanded that Tokyo pay a $200-million (170-million euro) ransom for Goto and Yukawa's release. Abe refused to bend to "terrorism."
IS had previously said it would allow Goto to go free in exchange for the release of Iraqi Sajida al-Rishawi by Jordan. Jordan, in return, demanded the release of one of its pilots currently being held by IS. There was no mention of the airman in Saturday's video.
Japan's PM vows justice
Harsh words emanated from Japanese Prime Minister Shinzo Abe, whose government had not been able to secure the safe release of the two victims.
"The government has been working with the utmost efforts on the issue - I deeply regret that this is the result," Abe said.
However, he reiterated that Tokyo would not yield to the terrorist and that it would "never forgive terrorists."
"I feel strong indignation at this inhumane and contemptible act of terrorism," Abe said, adding that Tokyo would "cooperate with the international community to make [the perpetrators] atone for their crimes."
While Japan is not participating in the military campaign against IS, it recently vowed billions in non-military assistance to Middle Eastern countries affected by the Syrian war and the expansion of IS through parts of Syria and Iraq.
In late August, the terrorist group beheaded American James Foley, the first in a series of gruesome executions of captives whose countries are involved in the US military campaign. They include Americans Steven Sotloff and Peter Kassig; Britons David Haines and Alan Henning; and Frenchman Herve Gourdel, who died at the hands of a jihadist group in Algeria with links to IS.
kms/rc (AP, AFP, Reuters, dpa)