Tokyo, Jan 25 (IANS): Japanese government spokesman Yoshihide Suga said Sunday that the latest video suggesting a Japanese hostage held by the Islamic State (IS) militants was killed is likely authentic, Xinhua reported.

He, however, added that Japan was still analysing is it was the IS which posted the clip. Suga said Japan will cooperate with Jordan and other countries to secure the safe release of the other Japanese held hostage by the IS, but added that Japan still had no contact with the hostage takers.

In the latest video with photo of Kenji Goto, a Japanese hostage, and an audio message posted late Saturday saying that Haruna Yukawa, the other Japanese hostage, was killed.

Japanese Prime Minister Shinzo Abe condemned the killing of Yukawa immediately after the video was released, criticising after a ministerial meeting on the issue that the killing was "an unforgivable act of violence."

The prime minister also demanded the release of Goto and prioritised his safety.

The latest video came after a clip shown Tuesday by IS militants demanding $200 million in ransom for the two Japanese hostages within 72 hours, the same amount pledged by Abe to the Middle East region to fight against the IS.

The video also said that the IS militants demanded the release of a female IS member imprisoned in Jordan. The prisoner reportedly launched a suicidal attack in Jordan in 2005 and killed about 50 people.

Secretary General of the ruling Liberal Democratic Party Sadakazu Tanigaki said Sunday that the government finds it "not easy to deal with" the IS's fresh demand as there is a rule against nations reaching deals with terrorists, according to Japan's Kyodo News.

Shoichi Yukawa, 74-year-old father of Haruna, told reporters that he was "distressed" by the latest development.

On Friday, Goto's mother also made a tearful press conference begging the release of her son and stressing that Goto is not an enemy of the Islamic faith. She also asked the Japanese government to try to save Goto.

Japan has set up a task force in Amman, Jordan, to deal with the hostage crisis.

Yukawa reportedly entered Syria in July last year from southern Turkey. He is said to have been travelling to Syria and Iraq, including conflict areas, to set up bases for his Tokyo-based company, the report said.

Goto, an acquaintance of Yukawa, went missing in October after he left for Syria to look for Yukawa.