A former top official of a state-owned gold and silver refining giant in north China's Inner Mongolia Autonomous Region has been detained for embezzling nearly 60 kilograms of gold and 1.4 tons of silver, and selling them in his jewelry stores.

Song Wendai, former chairman of the Qiankun Gold & Silver Refinery Share Co Ltd, was also discovered to have siphoned off 21 million yuan (US$3.32 million) of state assets since 2003 to found three companies of his own, according to prosecutors.

Since he came into power in the group nearly 10 years ago, reports have increased linking him with corruption. To deal with frequent police investigations, he had prepared a pleading in advance and carried it with him at all times, Xinhua news agency reported yesterday.

His careful preparation stymied police until prosecutors started to investigate him at the end of 2010, they said.

Song is a highly intelligent criminal, investigators said, and lax supervision made it easier for him to commit crimes.

For more than a year, police questioned nearly 200 people from 10 provinces to get conclusive evidence, Xinhua said.

In 2005, Song spent 15 million yuan purchasing a gold mine in Hohhot under the name of Qiankun with the help of local authorities while transferring the mine to his own company and then selling it to a Beijing company for 41.5 million yuan.

Officials said the corruption greatly damaged Qiankun, once the top gold and silver refinery company in China, Xinhua said.