Zhou Yongkang, who rose to become China's top policeman and a senior politician, made his name in the oil industry.
Mr Zhou, an engineer specialising in exploration, was previously general manager of the China National Petroleum Corporation, the country's largest oil and gas producer.
Before becoming head of China's Public Security Ministry in 2003, he was the party head in Sichuan Province.
While there, he gained a reputation for dealing firmly with any signs of dissent - coming down hard on Tibetan groups and the banned spiritual movement Falun Gong.
Mr Zhou, born in 1942 in Jiangsu Province, began his tenure as minister for public security by seeking to root out sloppy practices.
He sacked hundreds of police to stamp out a drinking culture, in a move analysts say helped to enhance the reputation of the force.
He has since endeared himself to the force by creating a more professional, more powerful body.
The ruthless streak he developed in his time in Sichuan also seems to have remained, and he has frequently expressed his willingness to crack down on what he has termed "hostile forces".