The Japanese government has no plans to withdraw troops from Iraq (search) despite a terror threat allegedly made by an Islamic militant group, an official said Wednesday.

An online statement attributed to the Tawhid and Jihad group Tuesday said that "queues of cars laden with explosives are awaiting" Japanese troops if Tokyo did not follow the example of the Philippines (search) and withdraw.

A Foreign Ministry official said Wednesday that the reliability of the report is being looked into amid media reports that the group later disowned the statement.

"Japan plans to continue its activities in Iraq," the official said on condition of anonymity.

"Japan is in Iraq on a humanitarian mission," she said. "The Iraqi people and government are grateful for its efforts."

Tawhid and Jihad is considered one of the most dangerous groups fighting coalition forces in Iraq. The group, led by Al Qaeda-linked militant Abu Musab al-Zarqawi (search), has claimed responsibility for attacks on U.S. troops and Iraqi police and security forces that have killed hundreds, as well as the beheadings of American, Bulgarian and South Korean hostages.