The ministry will look into whether the documents allegedly indicating Abe's "will" behind the plan by the Kake Educational Institution existed or not.

"We decided on the move after comprehensively examining the situation where many citizens are calling for an additional probe," Matsuno, who had been refusing to reinvestigate the case, told a press conference.

Matsuno said he has been told by Abe to swiftly carry out a thorough investigation.

The ministry will decide on methods and other details of the reinvestigation at an early date, he added.

At issue is the plan by the school operator based in the western city of Okayama to establish the department of veterinary medicine in a national strategic special zone in the city of Imabari, Ehime Prefecture, also western Japan.

Former vice education minister Kihei Maekawa has claimed the authenticity of the documents in question showing that the Cabinet Office urged the education ministry to accelerate work to approve the plan, citing Abe's will and the wish of the highest-level official at the prime minister's office.

Upon a request for a probe from the largest opposition Democratic Party, which obtained the documents, the education ministry interviewed officials of related departments and checked files saved in common folders in the ministry's computer system.

On May 19, the ministry announced that the existence of the documents in question could not be confirmed through the probe.

The DP demanded a reinvestigation by showing a copy of an email message noting that the documents were shared within the ministry. (Jiji press)