Seven ministerial-level officials were investigated for suspected embezzlement or bribery in China last year, according to the nation's procurator-general on Sunday.

Prosecutors nationwide investigated a total of 2,524 officials above the county head level, with 198 at the prefectural level and seven at the provincial or ministerial level, said Cao Jianming, the procurator-general, while delivering a work report at the annual session of the national legislature.

The prosecutors took a hard line on civil servants who abuse their power for personal gains or take bribes, investigating 7,366 people in the administrative law enforcement and 2,395 in the judiciary system, said Cao.

He said efforts intensified last year to crack down on the crime of offering bribes, with 4,217 bribery prosecutions, a year-on-year increase of 6.2 percent.

International judicial cooperation was enhanced as well, he said, retrieving a total of 7.79 billion yuan ($1.23 billion) of illicit assets and leading to the arrest of 1,631 fugitive suspects of work-related crimes.

Cao said greater emphasis was also put to the combination of punitive and preventive measures in 2011, with procuratorates at all levels launching extensive publicity campaigns to prevent work-related crimes.

He said this year the procuratorates will severely crack down on work-related crimes among officials, crimes seriously violating people's economic, personal and democratic rights, as well as cases involving construction projects, real-estate development, environmental pollution and food safety.

In a separate report to the parliamentary session on Sunday, China's chief justice, Wang Shengjun, said courts nationwide convicted 29,000 people for embezzlement, bribery and malfeasance last year, "further deepening the anti-corruption drive".

A total of 519 people in the court system were punished for violating discipline or laws, among whom 77 received criminal penalties for taking bribes or dereliction of duty, he said. The figures were down by 33.7 percent and 30.6 percent, respectively, on the previous year.