TOKYO, March 20 (Xinhua) -- Japanese Prime Minister Shinzo Abe has been under fire amid a deepening cronyism and document-tampering scandal, which has drastically brought down his cabinet's approval ratings, while people staged protests across Japan calling for the cabinet's resignation.

A cut-price land deal scandal implicating Abe and his wife Akie first came to light in February last year, when local media reported that Moritomo Gakuen, a private school operator, bought a 8,770-square-meter piece of land in June 2016 in Toyonaka, Osaka prefecture, for 1.26 million U.S. dollars, equivalent to only 14 percent of its appraisal price.

The scandal, after fading for some time since the ruling bloc's victory in the upper house election last October, has drawn renewed attention recently after local media reported that some finance ministry documents linked to the dubious deal appeared to have been revised in an apparent attempt to cover up the scandal.

Experts pointed out that the protracted scandal could seriously dampen Abe's chances of securing a third term as LDP (Liberal Democratic Party)President and in turn his chances of becoming the longest-serving prime minister in post-war Japan.

Japanese Prime Minister Shinzo Abe and Finance Minister Taro Aso attend an upper house Budget Committee session in Tokyo, Japan, March 19, 2018. (Xinhua/Ma Ping)

WIDENING SCANDAL

Lined up in front of parliamentary buildings in Tokyo, the impressively eye-catching banners with such slogans as "Abe and Aso have no shame!""Abe's cabinet should step down!" were firmly held by thousands of protesters shaking their fists in anger.

The protest was triggered by Abe's denial of either his or his wife's involvement in the cut-price land deal.

"I didn't know about even the existence of the finance ministry's internal settlement documents. I couldn't order the rewriting of them," Abe told an upper house budget committee session Monday.

Finance Minister Taro Aso, also deputy prime minister, said that a few officials in the ministry's financial bureau altered the documents without Abe's knowledge.

Aso's claim obviously has failed to blind the protesters.

"The government tries to hide the truth and distract people's attention from the scandal. We won't allow that to happen. We will continue to express our anger on behalf of the people," said Shingo Fukuyama, a member of a civil group that organized the protest.

People protest in front of the parliamentary buildings against the cronyism and document-tampering scandal and call for Prime Minister Shinzo Abe's cabinet to resign in Tokyo, Japan, March 19, 2018. (Xinhua/Ma Ping)

The protesters' opinions were also mirrored in recent media polls, which saw a plunge in the approval ratings of Abe's cabinet, with a majority of people believing that Abe can hardly absolve himself from the widely reviled document alteration.

According to a Kyodo News poll released on Sunday, the approval rate for the prime minister's cabinet dropped to 38.7 percent, down 9.4 percentage points from a previous survey conducted on March 3-4, while the disapproval rate stood at 48.2 percent, up 9.2 percentage points.

According to the poll, some 43.8 percent of the respondents said Abe should step down after more evidence came to light about the adverse impact of the shady land deal, and a total of 66.1 percent said Abe should be held accountable for the finance ministry's tampering of documents.

Another survey by the Asahi Shimbun showed that the cabinet's approval rate has plunged to 31 percent, the lowest ever in the newspaper's polling since Abe re-took office as prime minister in 2012.

Abe's approval rate was down 13 percentage points from 44 percent in a previous poll, while the non-support rate rose to 48 percent from 37 percent.

Japanese Prime Minister Shinzo Abe and Finance Minister Taro Aso attend an upper house Budget Committee session in Tokyo, Japan, March 19, 2018. (Xinhua/Ma Ping)

ABE'S THIRD TERM ENDANGERED

While experts believe that investigations to the scandal would last for weeks or even months with Abe holding on to power, they pointed out that the protracted scandal could seriously hurt Abe's chances of securing a third term as LDP president in the September election and in turn his chances of becoming the longest-serving prime minister in post-war Japan, as criticism was building up inside the party.

LDP Secretary General Toshihiro Nikai has said that doctoring the documents was a serious problem that was beyond imagination and could not be explained simply as a mistake.

LDP lawmaker Seiichiro Murakami, a strong critic of Abe, has reportedly called for Abe to resign last week.

Several polls also showed that Abe has fallen behind his main rivals inside the party regarding whom the voters would like to elect as prime minister.

According to a Kyodo poll, Shigeru Ishiba, former defense minister, was supported by 25.4 percent of respondents, followed by Shinjiro Koizumi, son of former Prime Minister Junichiro Koizumi, while Abe fell to the third from the first place in a February survey, with 21.7 percent supporting him.

Another poll by the Nippon TV also showed that Ishiba and Koizumi, with 24 and 21.2 percent of approval ratings, were far ahead of Abe's 14 percent.

People protest in front of the parliamentary buildings against the cronyism and document-tampering scandal and call for Prime Minister Shinzo Abe's cabinet to resign in Tokyo, Japan, March 19, 2018. (Xinhua/Ma Ping)

Takakage Fujita, a political analyst and head of a Japanese civic group dedicated to upholding and developing the well-known Murayama Statement, said that if the Abe administration fails to apologize to the people sincerely, the approval rating for Abe's cabinet could still go down, and Abe's rivals inside the ruling party might take some actions (in the upcoming party president election).

The Murayama Statement was released by the then Prime Minister Tomiichi Murayama on Aug. 15, 1995. In it, he apologized for the damage and suffering caused by Japan to its Asian neighbors during World War II.

Ukeru Magosaki, a former senior official with the Japanese foreign ministry, said that document tampering constitutes a crime under Japanese law and those associated with it should be held accountable.

He added that if Aso, a close ally of Abe and a key member of the Abe administration, steps down to take responsibility as the public calls for, it would significantly weaken the Abe government.

The resurgent scandals also trigger concerns over Abe becoming a lame duck in carrying out his major policies.

(Jon Day in Tokyo also contributed to the report.)