Four former senior officials have been charged with bribery and corruption by prosecutors, the Supreme People's Procuratorate said on Monday.

Le Dake, former deputy head of the Standing Committee of the Tibet autonomous region's People's Congress, has been charged with bribery by the Zhengzhou city people's procuratorate in Henan province, which will prosecute the case at Zhengzhou Intermediate People's Court. A date for the court hearing will be set later.

According to an indictment, when Le served as director of the autonomous region's State Security Bureau and head of regional legislature, he abused power to gain benefits for others and accepted huge bribes paid in cash or other assets.

"During the investigation and prosecution, prosecutors informed him of his rights and carefully listened to his lawyers' defending opinions to protect his legitimate rights," according to a statement provided by the SPP on Monday.

In a separate development, Wang Tianpu, former general manager of oil giant China Petroleum and Chemical Corp, has been charged with corruption and bribery by the Nanchang city people's procuratorate in Jiangxi province.

Prosecutors said that when he served as general manager and CEO, he abused power to benefit others and accepted huge bribes.

In addition, Si Xianmin, former general manager of China Southern Airlines, has been accused of accepting bribes by the Shenzhen city people's procuratorate in Guangdong province; and Wang Shuaiting, former vice-chairman of China Travel Services Hong Kong, has been charged with corruption and bribery by the Shenzhen city people's procuratorate.

Tackling graft has become a top priority for the country since late 2012. President Xi Jinping has launched a sweeping campaign to target high- and low-ranking officials, or "tigers and flies".

To date, more than 140 high-ranking officials suspected of corruption have been placed under investigation, including Zhou Yongkang, former security chief, who was sentenced to life in prison in June 2015.