The education ministry's former top bureaucrat fired up the simmering Kake Gakuen scandal at a news conference Thursday by vouching for the authenticity of documents that suggest Prime Minister Shinzo Abe swayed its decision to approve the opening of a new veterinary medicine department run by his friend at a university in Shikoku.

The government flatly denied Abe was involved in the decision, and the ruling coalition led by his party spurned a call by the opposition camp to summon former Vice Education Minister Kihei Maekawa as an unsworn witness to the Diet.

"I'm sure that the documents did exist," Maekawa told a news conference on Thursday afternoon in Tokyo.