Some people collect stamps, others memorabilia, model trains or Pokeman cards.

For former official Huang Peng, his hobby was collecting cold hard cash - like the HK$2.2 million ($322,300) police found in his bedroom when they searched his house last year.

Huang, 43, the former deputy director of Guangzhou Development District's planning, land and construction bureau, is on trial on charges of corruption.

Huang is charged with receiving bribes of more than 500,000 yuan ($73,000) between 2002 and 2008 and holding property from unclear sources worth HK$1.76 million. Huang has admitted to receiving bribes but argued against the charge of holding a huge amount of property from unidentified sources.

According to Huang's lawyer, who refused to be identified, Huang and his wife had monthly salaries of about 40,000 yuan and the assets of his family must have added up to about 6.5 million yuan in the past two decades.

"As far as I calculate, Huang's family must have disposable capital of abut 2.7 million after the deduction of expenditures on house purchase and decoration as well as daily expenditures," he said.

According to the Guangzhou Daily, Huang's bribes came primarily from two village officials of Guangzhou Development District. They have also been arrested and their judgments are still pending.

At a recent conference, Su Zhijia, secretary of the city disciplinary committee, said that young and middle-aged officials are the most vulnerable to corruption.

"Some lawbreakers are targeting young and middle-aged officials and try to make friends with them even when they are not in important positions," Su said.