HANOI, Vietnam (AP) — The head of Vietnam’s parliament has resigned, according to state media, making him the latest senior member of government to leave office amid an ongoing anti-corruption campaign that's shaken the country's political and business elites.

The resignation of National Assembly Chair Vuong Dinh Hue adds to growing instability in the country. President Vo Van Thuong resigned in March — just over a year after the previous president, Nguyen Xuan Phuc, resigned to take political responsibility for corruption scandals during the pandemic.

“It also highlights the extreme uncertainty in a political environment that's often boasted of its stability, as three top leaders have been axed in just a year,” said Nguyen Khac Giang, an analyst at Singapore’s ISEAS-Yusof Ishak Institute.

Hue's resignation came days after his assistant Pham Thai Ha was arrested on charges of abusing his position and power for personal gain on April 21, according to state media outlet VN Express.

Initial reports did not say that Hue was implicated in corruption, but noted that investigators found that the parliamentary leader had “violated Party regulations, and his violations have affected the reputation of the Party, the State and himself.” Vietnam’s Communist Party accepted what it called a voluntary resignation from Hue, according to VN Express.

Hue, 67, had been the chair of Vietnam’s national assembly for over three years. That made him the fourth most important politician in Vietnam, along with the President, the Prime Minister and the head of the Communist Party.

Political instability could threaten Vietnam’s economic ambitions as it vies to become an alternative to China in the region’s supply chain. On a visit to Vietnam earlier in the month, Apple CEO Tim Cook said he wants to further increase investment in the country.

Ha’s arrest resulted from an expansion of the ongoing investigation into the Thuan An Group, said Vietnam News Agency, citing Ministry of Public Security spokesperson Lt. Gen. To An Xo. Company chair Nguyen Duy Hung and several others were arrested earlier in April.

The Blazing Furnace campaign has singed businesses, and led to an unprecedented death sentence for real estate tycoon Truong My Lan in Vietnam’s largest-ever fraud case.

Giang, the analyst, said Hue was previously seen as a likely successor to Trong. “His downfall will only intensify Vietnam’s succession crisis,” he said.

Vietnam’s leaders are next due to convene a Communist Party congress in early 2026.

Meanwhile, experts say, rivals are jostling to position themselves as a successor to Trong, who was elected to an unprecedented third term as party chief in 2021. Given his age, experts say that it is unlikely that he will continue for another term.