Beijing - China has arrested a senior journalist working for Singapore's Straits Times newspaper who was trying to obtain a sensitive manuscript of secret interviews with deposed Chinese leader Zhao Ziyang.

Ching Cheong, 55, chief China correspondent for the paper, was detained on April 22 in the southern city of Guangzhou and authorities were preparing to charge him with “stealing core state secrets”, his wife Mary Lau said yesterday.

“It's because of Zhao Ziyang… China is trying to prevent the manuscript from being published. They think it's very sensitive.”

The manuscript recorded interviews conducted by Zong Fengming, a former Xinhua news agency reporter who had rare access to Zhao before his death in January.

Zhao, a former premier and general secretary of the Communist Party, was purged in 1989 after opposing the decision to use force to quell the six-week-long Tiananmen Square democracy protests that year.

Hundreds, if not thousands, of unarmed protesters and citizens were killed during the crackdown and Zhao spent the rest of his life under house arrest.

Zhao had no access to his former close associates but Zong was able to see him as a qigong, or Chinese meditation master.

Zong had published a memoir last year in which he quoted from his interviews with Zhao and indicated he was preparing a second book titled Conversations with Zhao Ziyang in House Arrest.

Lau said Cheong was the first journalist to gain access to Zong's memoirs and write about Zhao's remarks.

Lau said Zong's editor had asked her husband to help him take the manuscript for the second book out of mainland China so that it could be published.

Her husband had been trying for months to obtain the manuscript, she said.

“He went to Guangzhou thinking he would get the manuscript from a mediator, but we believe he was set up. I was told that as soon as he was handed the manuscript - which might not have been the real thing - at a hotel, state security officers detained him.”

Lau was later told that officials were preparing to charge him with stealing state secrets, a charge the government often uses to stop people from, or punish them for, accessing information it considers too sensitive.

Zhao's inside knowledge of what led to the decision by Chinese leaders to order troops to open fire on the Tiananmen Square demonstrators would be explosive material in China.

Details of that bloody chapter in Chinese history are still banned from Chinese media and school textbooks.

Chinese officials did not comment on Monday.

A spokesperson for Singapore Press Holdings, the publisher of the Straits Times, said Chinese officials had informed the company that Cheong was being detained.

Singapore's Foreign Ministry said it had not been contacted by China. Cheong is a permanent resident of Singapore but a Hong Kong citizen.

Cheong's arrest may be part of a broader investigation to prevent the manuscript from being made public. - Sapa-AFP