The suspended officer, Admiral Miao Hua, served on the ruling Central Military Commission, China's highest-level military command body, and was stationed in the coastal province of Fujian when President Xi Jinping worked there as a local official, according to his official biography.

Miao, 69, who began his career in the army, has been the military's leading political officer given his role on the six-person commission, which is headed by Xi.

A defence ministry spokesperson, Wu Qian, who briefed reporters at a monthly press conference in Beijing, provided no further details.

China's military has undergone a sweeping anti-corruption purge since last year, with at least nine People's Liberation Army generals and a handful of defence industry executives removed from the national legislative body.

Wu said media reports that Dong had been sidelined by an investigation were "sheer fabrication" spread by rumour-mongers with evil motivations.

The Financial Times reported this week that Dong was being investigated as part of the wide-ranging anti-corruption investigation, citing current and former U.S. officials.

Two U.S. officials told Reuters they believed Dong was being investigated for corruption. Another urged caution about that conclusion.

Dong had declined last week to meet U.S. Defense Secretary Lloyd Austin during a meeting of defence ministers in Laos, citing U.S. actions over Taiwan, a move the Pentagon chief said on Wednesday was unfortunate.

Asked about the decision not to meet Austin, Wu cited Dong by name as saying the United States had been "seriously undermining regional peace and stability."

Dong was appointed defence minister in December 2023, replacing Li Shangfu, who was removed after seven months.

Li and his predecessor, Wei Fenghe, were expelled from the Communist Party in June for "serious violations of discipline", a euphemism for corruption.

Many of those ousted earlier were from the Rocket Force - an elite arm of the PLA that oversees its most advanced conventional and nuclear missiles.

Analysts said at the time that exposing deep-set graft could take time and potentially slow Xi's long-running military modernisation plans.

Diplomats and analysts are watching closely for any signs the campaign could hamper ongoing military operations, commands and the PLA's diplomacy.

China security scholar James Char said on Thursday that Miao was a Xi "acolyte".

"Clearly, Xi Jinping's trust in yet another of his uniformed subordinates has been misplaced," said Char, of Singapore's S.Rajaratnam School of International Studies.

"If Miao Hua is eventually found guilty, the CMC Chairman himself probably failed to size up the extent of corruption among China's military elites."

The latest Pentagon report on China's military, issued in October 2023, said Miao "may have ties" to Xi from his time in Fujian.