Archives relating to recent historical events and people, such as the June 4 incident and former party chief Zhao Ziyang , have been kept intact despite controversies surrounding them, according to a leading archivist. Liu Guoneng , former deputy director-general of the Communist Party Central Committee's archives office and that of the State Council, said the mainland led the world in terms of the number and size of its archives offices, the scale of the collection and their management. In a rare interview with overseas media, Mr Liu, a CPPCC member, was keen to dispel notions that archives relating to controversial figures and periods in the history of the Communist Party were doctored or destroyed. The ruling party and the government had built an up-to-date and complete archives system, in which all important original historical documents, papers and records from officials and governments at various levels had been basically kept intact. Mr Liu said material relating to late party chief Zhao was sent to the central archives bureau directly under the General Office of the party's Central Committee after his death. He said the mainland had perfected its system of archiving material on national leaders and ministers. Archives dealing with deceased leaders, including Deng Xiaoping , Hu Yaobang and Zhao, were all kept in the central archives office, while the archives of ministers were kept by the State Bureau of Archives. 'The nature of archives work dictates that all original documents, papers and records should be kept, rather than material written later by other people,' Mr Liu said. 'Books and biographies all feature the views of the author. But archives are historical evidence.' Mr Liu said all central government ministries, agencies and organs, and all governments down to the county level, had archives offices. He said the government had sped up the process of declassifying historical archives. And in practice, many classified historical archives were opened up for academic research before they were declassified. 'Generally, the law and regulations suggest that historical archives could be opened to the public in 30 years, which is in line with practices in many countries,' Mr Liu added. However, he admitted that the mainland process was selective in consideration of political sensitivity, sovereignty issues and state and military secrets. Mr Liu said it might take longer to declassify archives relating to the events of June 4, Zhao, and even late chairman Mao Zedong and the Cultural Revolution he launched.