The president of China's third-biggest lender by assets, Agricultural Bank of China Ltd (AgBank), has been taken away to assist with an investigation, Bloomberg reported on citing people familiar with the matter.

The probe is the latest revelation in President Xi Jinping's ongoing corruption investigations that have already ensnared top politicians, state enterprise leaders and a cast of senior bankers, including AgBank's former vice president, who was jailed for life for graft, and a board director at the Bank of Beijing.

Local media outlet Sina Finance also reported earlier on Monday that police took Zhang Yun, 56, away to "assist with investigations" - a euphemism commonly used to indicate a person is being probed for graft.

Bloomberg said the people familiar with the matter did not say who was conducting the investigation or its purpose.

Reuters was unable to verify the reports. Telephone calls to AgBank were left unanswered.

An inspection team from the ruling Communist Party's anti-graft watchdog visited AgBank's headquarters on Monday and Zhang Yun was not present, Sina Finance said.

The graft probes into the financial sector are part of Xi's broader campaign to root out corruption at major state-run firms and within government ranks, including in the military and domestic security forces.

China's finance industry executives have been caught up in separate investigations into stock market manipulation after stocks at the country's two main bourses slid almost 50 percent at one point since mid-June.

China arrested executives at a Hong Kong-owned fund for futures manipulation, in a crackdown on trading activity seen by regulators as destabilizing the market.

In February, a Chinese court jailed Yang Kun, the former vice president of AgBank, for accepting more than 30 million yuan ($4.73 million) in bribes, including works of art and gold bars.