Zhou meets with student volunteers during China University of Petroleum's anniversary on Oct 1, 2013. [Photo/ cup.edu.cn]

Zhou Yongkang, a former member of the Standing Committee of the Political Bureau of the CPC Central Committee, was last seen in public at the 60th anniversary of his alma mater, China University of Petroleum, on Oct 1, 2013.

Zhou, also former secretary of the Commission for Political and Legal Affairs of the CPC Central Committee, returned to the university and visited the school's history museum. He also spoke with students and attended a reunion with his old classmates, according to the university website.

Between 1961 and 1966, Zhou studied geography at the university, which was then known as Beijing Petroleum Institute.