A top official who led China's biggest petroleum company and later was assigned to oversee state-owned companies admitted in court Monday that he was guilty of corruption and abuse of power, the court said.

"My family property went far beyond what my legal income could afford," said Jiang Jiemin, according to a statement posted on the microblog of the Hanjiang Intermediate People's Court in Hubei province. "I admit my crimes and express my regret."

The hearing ended Monday afternoon and a date for sentencing was not announced.

Jiang is a former chairman of the state-run China National Petroleum Corp., or CNPC, which has been the target of a sweeping graft investigation amid a larger anti-corruption campaign that has netted top officials and others.

Jiang was charged with taking bribes, possessing a large number of assets from unidentified sources and abusing his position at a state-owned enterprise. The court said on its microblog that prosecutors had presented evidence including witness statements, confessions and confiscated items, without giving details, and posted a photo of a pale-faced Jiang in the dock flanked by two police officers.

It quoted Jiang as saying he had caused "undeniable damage" to the country and hurt the public's trust in the Communist Party.

"I sabotaged the management and development of state oil and gas fields," he said, according to the court, while also asking for lenient treatment.

Jiang was chairman of CNPC, the parent company of PetroChina Ltd., Asia's biggest oil producer, before being appointed in 2013 to the Cabinet body that oversees China's biggest state-owned companies. He was fired from that post in September 2013 after he came under investigation.

A series of senior figures from the state-owned oil industry have been detained in the crackdown led by President Xi Jinping that appears to be aimed at tightening central control over PetroChina and other powerful state companies.

The energy industry was a power base for Zhou Yongkang, the ruling Communist Party's former security chief, who was arrested in December on charges including bribery and leaking state secrets. Control over state companies can provide political figures with jobs to reward supporters and money to promote their own careers.

Jiang was believed to have links to Zhou, although prosecutors have not cited any link between the two cases.