Sun Hung Kai Properties Executive Director Thomas Chan Kui-yuen (3rd R) arrives at the High Court in Hong Kong May 8, 2014. One of Hong Kong's largest corruption trial on Thursday begins as Sun Hung Kai Properties' billionaire brothers Thomas and Raymond Kwok, and the city's former number two official Rafael Hui appear in court.[Photo/Agencies]

HONG KONG -- A corruption trial involving Hong Kong's former chief secretary Rafael Hui and two of the city's richest men Thomas Kwok and Raymond Kwok opened in Hong Kong Thursday.

Hui, 66, the most senior official ever charged of graft in Hong Kong, is accused of accepting $HK34 million (about $4.39 million) from the Kwok brothers, who jointly chair one the world's major developers Sun Hung Kai Properties, in exchange of land sales information.

Hui and the Kwok brothers were arrested by the city's graft- buster Independent Commission Against Corruption in March 2012. The three were among five people charged with eight offences including misconduct in public office and furnishing false information. All pleaded not guilty.

The trial is expected to last for 70 days, with evidence of more than 80 prosecution witnesses.