Former land official Yin Guoyuan and his wife are being investigated for being unable to account for their wealth, including several properties, Shanghai newspapers reported yesterday. Mr Yin, former deputy director of the Shanghai Housing and Land Administration, was being investigated by the Shanghai Commission for Discipline Inspection for violating the law and Communist Party rules, the Oriental Morning Post and Shanghai Daily reported. Mr Yin, who held his position for 10 years before stepping down in 2005 to head an industry group, held the power to approve land transfer contracts. Reports quoted government sources as saying the land leases boomed during Mr Yin's tenure, while the official himself talked up the market by saying property prices would not drop. Authorities sacked Shanghai Party Secretary Chen Liangyu last September over his role in a corruption case which involved misappropriation of the city's pension fund. A new Shanghai party secretary, Xi Jinping , took over last month. Another land official, director of the Shanghai Housing and Land Administration's land use management section Zhu Wenjin , was detained last November for allegedly accepting bribes. Several others are said to be under investigation, including a former government official now working for a Hong Kong developer, the Shanghai Securities News reported. One property industry official said the appointment of the new party secretary had led many to believe the corruption investigation was drawing to an end. 'I thought they had put an end to it,' he said. Shanghai officials had vowed to improve transparency of land sales following a dispute over relocation amid allegations of bribery, but no government officials were ever punished in that case.