Former security chief Zhou Yongkang is suspected to have established close connections with other allegedly corrupt officials, according to a magazine website report.

Zhou allegedly formed links with Xu Caihou, the former vice-chairman of the Central Military Commission, and Ling Jihua, former minister of the United Front Work Department of the Communist Party of China Central Committee, the Caijing.com.cn report said.

Xu died of bladder cancer on Sunday.