BEIJING - A former senior political advisor from Hunan province was sentenced to five years in prison for neglect of duty in one of the largest election frauds in China.

Tong Mingqian was convicted of failing to investigate and stop a large-scale election fraud while serving as the leading official of Hengyang city in Hunan, the Beijing Second Intermediate People's Court said in a statement of verdict.

Tong was implicated in the fraud involving more than 500 lawmakers between Dec 28, 2012 and Jan 3, 2013. Then secretary of the Communist Party of China (CPC) Hengyang City Committee, Tong was responsible for organizing the election for the city's deputies to the provincial people's congress.

During the election, he was reported that some candidates offered bribes to buy votes but took no measures to stop the illegal practices. He also failed to organize an investigation into the fraud after the election, as he was required to do by law, the court said.

When the scandal was exposed, Tong had been promoted to vice chairman of the Hunan Provincial Committee of the Chinese People's Political Consultative Conference.

The fraud is one of the largest in terms of people and money involved. Investigations showed 56 candidates from Hengyang bribed 518 lawmakers and 68 staff for the election of deputies to the Hunan provincial people's congress. The amount of money involved in the bribery exceeded 110 million yuan ($18 million).

Tong was expelled from the CPC and dismissed from public office in January.