TOKYO - Hundreds of students and citizens rallied in front of a parliament building Thursday evening to protest against a school land deal scandal that involves Prime Minister Shinzo Abe and his wife Akie, after a key figure in the scandal testified in parliament earlier in the day.

The protestors, from some 40 different civil groups and many of them college students, gathered in front of the parliament building, holding banners written with slogans such as "Moritomo incident shall be thoroughly investigated" and "Abe shall step down".

"Moritomo Gakuen President Yasunori Kagoike read out a fax sent to him by a secretary of Mrs. Abe when testifying in the parliament this afternoon. It shows a possibility that Mrs. Abe was directly involved in the incident," said Mizuho Fukushima, a lawmaker from the Social Democratic Party, at the rally.

She called on the parliament to go to the bottom of the incident and to summon Akie Abe and other related figures to testify in the parliament.

She also expressed concerns that the Abe administration uses intimidation methods to deal with criticism and opposition, saying that people shall strongly oppose such an administration.

Protestors there also voiced their opposition to the nationalist, imperialistic-styled school education indulged by Abe administration, as embodied by the education principle of the scandal-hit Moritomo Gakuen.

"The kindergarten run by Moritomo Gakuen required students to memorize the Imperial Rescript on Education, an edict that was used to promote emperor-oriented and militaristic education before and during the WWII.

The school also preached that controversial war laws passed by Abe administration were justified. I think kids receiving such education would go down the wrong road," said Yuhara, a protestor from New Japan Women's Association at the rally.

"We shall not allow schools like Moritomo Gakuen to pump ultra-right wing thoughts into the minds of our children. We sacrificed a lot to have our current pacifist Constitution. But now the prime minister himself is promoting education that runs against the Constitution. It's a very severe problem," she added.

"It's no different from the education provided by militaristic Japan before the end of WWII. We strongly oppose such education," said Hirokawa, a senior student from Waseda University.

Hiromori Maedomari, professor at Okinawa International University, said at a seminar in the parliament building ahead of the rally that he does not agree with the education principle of the nationalist school run by Moritomo Gakuen either.

Hideo Sugimoto, a lawmaker from the Democratic Party, said at the seminar that although Kagoike's testament was not yet verified, there has been some evidence showing the possibility of the existence of such a donation. "We shall go deeper into the incident and find out the truth," he said.

Moritomo Gakuen, a private-school operator, reportedly bought a 8,770-square-meter piece of land last June in Toyonaka, Osaka Prefecture, for 134 million yen (1.2 million U.S. dollars), equivalent to only 14 percent of its appraisal price.

The land had been intended for a new elementary school to be opened in April with the prime minister's wife Akie as its honorary principal, though she has since stepped down as the scandal widened.

Akie Abe also visited a nationalist kindergarten run by Moritomo Gakuen several times and gave speeches there. The kindergarten has been under fire for imposing on its students imperialistic-styled education and hate speech about Korean and Chinese residents of Japan.

Yasunori Kagoike, head of the school operator, testified under oath in both chambers of parliament on Thursday that he received 1 million yen (8,900 U.S. dollars) from Akie.

He also said that he had asked Akie Abe for help for building the elementary school and his wife had exchanged 22 emails with Akie Abe last month, and the recent emails could be taken as an attempt to silence him.

Kagoike, the first sworn witness summoned to the Diet since April 2012, could be charged with perjury if he gives false testimony.

Japan's top government spokesman Yoshihide Suga said at a press conference on Thursday that neither the prime minister nor his wife had made any donation to Moritomo Gakuen.

Abe himself has on many occasions denied involvement in the land deal.

The scandal, however, has been eroding Abe's support rates and presents the most serious crisis for the prime minister since he returned to office in 2012, according to some analysts.

According to a recent poll by Nippon News Network (NNN), support rate for the prime minister's cabinet dropped to 47.6 percent, down 7.3 percentage points from last month, while the disapproval rate increased 6.9 percentage points to 32.9 percent.

A different poll by Yomiuri Shimbun, one of the largest newspapers in Japan, showed that support rate for Abe's cabinet dropped 10 percentage points to 56 percent compared to one month ago.