BEIJING (AFP) - China is probing a retired top air force general on suspicion of graft, media said, the latest high-ranking official brought low by the country's much-publicised anti-corruption campaign.

Tian Xiusi, formerly the air force's political commissar, was "placed under investigation for serious disciplinary violations", www.81cn.com, an official news site affiliated with the People's Liberation Army, said at the weekend.

The expression is often used as a euphemism for corruption. The article provided no further details about the probe.

Since coming to power, China's President Xi Jinping has moved to ensure the ruling Communist Party's control over the military and loyalty in its ranks.

During his time in office nearly 50 senior officers in the PLA and the armed police, including the military's former number two and three figures, Guo Boxiong and Xu Caihou, have been convicted or investigated on corruption allegations.

China's military has significant business interests in sectors ranging from property and logistics to telecommunications and healthcare, which have become a hotbed for corruption.

Xi, the son of a revered revolutionary, is said to have closer links to the armed forces than his predecessor Hu Jintao.

But in March authorities ordered them to stop providing "paid services", or commercial activities, in around three years.

Tian began his military career in 1968 and held positions including political commissar in the mainly Muslim region of Xinjiang, before becoming the air force political commissar last year, the state-run China Daily reported Monday.

Tian's wife and secretary have also been placed under investigation, it said, quoting Chinese media reports.

In May, China's Central Military Commission announced that it had sent 10 teams of inspectors to investigate the PLA, the first time the supreme military command established a standing anti-corruption force.