The Islamic State group's threat Tuesday to execute two Japanese hostages is a chilling echo of a series of hostage crises involving Japanese citizens in 2004, including one that resulted in the victim being decapitated.

In an online video, a knife-wielding militant with a British accent said the group will execute the two, whom the video subtitles identified as Kenji Goto and Haruna Yukawa, unless Tokyo paid a $200 million ransom within 72 hours.

In a gruesome October 2004 case involving Islamist militants in Iraq, 24-year-old tourist Shosei Koda was killed. The group holding him had posted a video demanding the withdrawal of the Self-Defense Forces from the country within 48 hours.

The administration of Prime Minister Junichiro Koizumi rejected the demand, and Koda was decapitated.

In April 2004, three Japanese were released after eight days in captivity in Iraq.

The three, Tokyo photojournalist Soichiro Koriyama, 32, volunteer aid worker Nahoko Takato, 34, of Chitose, Hokkaido, and recent high school graduate Noriaki Imai, 18, of Sapporo, had been kidnapped by a terrorist-related group that demanded that SDF troops be withdrawn within three days.

In August 2012, Mika Yamamoto, an award-winning veteran journalist, was killed during a clash in Aleppo in northern Syria, where rebels and forces loyal to the Syrian government were fighting.

Other deaths in Iraq included the killings of two Japanese diplomats in an ambush in November 2003, and the deaths of two journalists at the hands of unidentified assailants in May 2004.