A record company on Tuesday has denied accusations that it has been leaking national secrets through its project of digitizing audio files during the Cultural Revolution (1966-76).

The project involves 54 original master copies of the speeches of some political figures during the Cultural Revolution, which had been made public at that time, according to a statement released by the China Record Corporation (CRC).

Cui Yongyuan, a popular former China Central Television host, said on his Sina Weibo account on Monday that the CRC turned over the master copies, which he said "obviously involved national secrets," to a Sino-Japanese joint venture company for digitization.

Cui said he had to report the case to the police by giving the official account of the Beijing Municipal Public Security Bureau.

His post has been reposted 7,100 times as of press time.

Photos posted along with the text showed that the files contained speeches of Jiang Qing, wife of Mao Zedong.

CBM Audio Visual Co Ltd, CRC's holding company, admitted that it digitized those documents. "Although two Japanese companies are also major shareholders, we don't have Japanese employees," a business director surnamed Wang with CBM Audio Visual told the Global Times.

"We've sent all the copies back to CRC after we finished digitalization," Wang said.

Cui claimed that the project violated China's regulations on outsourcing documents for digitization.

Safety regulations on outsourcing digitization, issued by the State Archives Administration of China in January, states that authorized persons of institutions digitizing documents have to be registered in China, and the shareholders have to be Chinese citizens.

The CRC statement said that the CBM's legal representative and employees are all Chinese, but it did not mention the two Japanese shareholders.

Digitizing those files is part of a national project of building a digital database of China's old albums started by CRC in 2012, according to Wang.

The project will digitize a total of 140,000 albums and audio files from the 1920s to 1990s, and is listed as a key national project in China's 12th Five-Year Plan (2011-15), according to the CRC.

Zhang Zhiqiang, a lawyer of the Beijing Yixing Law Firm, told the Global Times that the company's shareholders are entitled to apply to check the documents, including the Japanese shareholders.

Beijing police did not respond to Cui's report as of press time.