Two senior officials have been placed under investigation for suspected corruption as the nationwide anti-graft campaign is picking up steam.

The Central Commission for Discipline Inspection on Wednesday announced the investigation into Lu Ziyue, mayor of Ningbo in Zhejiang province, and Wang Yang, vice-chairman of the Liaoning People's Congress.

The commission, China's top anti-graft body, made two brief statements immediately after the 12th National People's Congress concluded its annual meeting, saying they are being investigated for "serious violations of Party discipline", a phase that usually refers to corruption.

No detailed information about their charges was available as of press time.

Lu, 54, also a deputy secretary of the Ningbo committee of the Communist Party, spent his entire career in Zhejiang province.

He held positions as the mayor or deputy Party chief as well as other senior posts in several cities in the province, including the mayor of Yiwu, a manufacturing and trading hub for small commodities.

According to public records, he was the deputy governor of Zhejiang province from January to May 2013 before he was appointed deputy Party chief and the acting mayor of Ningbo in May the same year.

Wang, 59, has held a host of positions in governments at city and provincial level in Liaoning province for more than 30 years. He worked in Anshan, a city known for its iron and steel industry, for most of the time and was the mayor of the city from 2011 to 2012.

He became the Party chief in Fuxin, Liaoning province, in 2012 before he was elected as vice-chairman of the Liaoning People's Congress in January 2013.

The probes are the latest efforts of the top disciplinary authority since it started a sweeping anti-corruption campaign in late 2012.

By the end of last year, more than 120 officials at or above minister level have been held under investigation and nearly 24,000 Party officials as well as government functionaries were disciplined last year.

Two weeks ago, the commission announced the investigation of Wang Min, vice-chairman of the Education, Science, Culture and Public Health Committee of the 12th NPC.