Beleaguered Defense Minister Tomomi Inada announced Friday that she will resign over allegations that a cover-up was conducted to hide the politically sensitive activity logs of the Ground Self-Defense Force unit that was deployed for peacekeeping duty in conflict-riven South Sudan.

Inada’s resignation will deliver another punch in the gut to the scandal-tainted administration of Prime Minister Shinzo Abe, who has for several months and despite repeated lapses consistently stuck up for Inada, widely considered his protege.

“Not only has the log controversy highlighted inappropriate handling of information disclosure, but the fact that there were numerous instances of what appeared to be information leakage from within our organization has risked eroding public trust in our governance system,” Inada told a packed news conference Friday.

“As someone who is in a position to oversee the Defense Ministry and the SDF, I feel a very deep sense of responsibility for all this. I have thus decided to step down as defense minister,” she said, adding that, as a gesture of contrition, she will voluntarily return one month’s salary.

That Inada bowed out voluntarily, rather than face outright dismissal, appears to be part of an effort by the administration to downplay the severity of the affair to minimize damage to the Cabinet, which is expected to be reshuffled next week.

On Friday, Chief Cabinet Secretary Yoshihide Suga sought to cast Inada’s resignation in a somewhat positive light, attributing it not to her blunders — which include politicizing the SDF during an election campaign — but solely to her voluntary desire to take responsibility for the log scandal.

Her resignation, however, by no means heralds an end to the political turmoil that has rocked Abe in recent days and weeks. The opposition is determined to convene an ad hoc session of the Diet where they can demand further explanations from Inada herself.

“I bear all the responsibility for giving her the portfolio in the first place,” Abe told reporters earlier in the day. “I believe I must humbly accept any criticism leveled at my Cabinet ministers.”

Regarding Inada’s replacement, Abe said he had asked Foreign Minister Fumio Kishida to temporarily step in as defense chief to avoid a vacuum in the critical post as tensions in the region build over North Korea’s provocative weapons tests.

Inada remained emphatic that she played no part in the alleged concealment of the logs, citing the conclusion of a months-long internal probe on Friday that found she never approved any wrongdoing.

The controversy dates back to March, when reports emerged that activity logs detailing the situation in South Sudan had been retained by the Ground Self-Defense Force despite an earlier assertion by the defense ministry that they had been discarded.

The logs are considered a barometer for determining whether the troops were in a combat situation. Any acknowledgement that they were facing combat would imply that Japan’s conditions for deploying troops overseas were being contravened — a particularly sensitive issue in light of Japan’s strictly pacifist stance on defense.In a Diet appearance in March, Inada originally said that she’d had no inkling of the apparent cover-up. But her earlier statements were questioned this month when fresh reports emerged that, during two closed-door meetings with top Self Defense Force officials in February, she consented to a plan to overlook the unexpected discovery of copies of the data.

On Friday, a report on the months-long internal investigation into the allegations concluded that, based on the officials and staff involved, Inada “made no decision” over whether to conceal the logs during the Feb. 13 and 15 meetings with SDF officials.

Isao Koba, an official involved in the probe, said all the interviewees denied at the hearings that Inada approved a cover-up.

The report acknowledged that it was “possible” GSDF officials had explained to Inada in the meetings that the logs existed, but it stopped short of drawing a clearer conclusion, based on the testimony given by Inada and others suggesting that such a conversation never took place.

“We could not corroborate” Inada’s involvement due to conflicting testimonies, Koba said.

Instead, the investigative body held Tetsuro Kuroe, administrative vice minister of the Defense Ministry, accountable for concealing the logs. It said that upon learning the logs had been retained by GSDF in February, the top bureaucrat decided not to disclose them on the basis that the same set of files had already been released by the SDF’s Joint Staff. Kuroe had resigned as of Friday.

Among others subject to disciplinary steps were the GSDF’s chief of staff, Toshiya Okabe, who faced a pay cut, and Masayoshi Tatsumi, administrative vice chief of staff for the SDF Joint Staff, who was suspended for two days.

Inada has carved out a colorful political career since being elected to the Diet in 2005. Her conservative ideology won her the tutelage of Abe, who assigned her to a series of important posts — including policy chief of the ruling Liberal Democratic Party — despite her inexperience. She had even been hailed as a potential future prime minister.

Staff writer Reiji Yoshida contributed to this report.