Exposed: New book reveals the dark secrets of China's history

The editors of a new book that they say exposes the secrets and dark side of mainland China under communist rule have expressed hopes that Hong Kong will remain a window for mainlanders to learn the truth.

National Secrets, launched on Monday in time for the Hong Kong Book Fair, is likely to be banned on the mainland as it covers sensitive topics such as the Dalai Lama's exile, the power struggle between the Communist Party and Kuomintang, and former premier Zhao Ziyang , who was put under house arrest after losing power.

"The freedom of Hong Kong is very important to us," compiler Sasha Gong, an academic who heads the Chinese branch of Voice of America, said. "Hongkongers should defend what they have, as history tells us freedom and democracy can be lost on a whim if you don't fight for it."

The Chinese-language book is a print version of information broadcast in a VOA programme entitled Leaking Moment. Its extensive research restored what Gong called a "missing part" of Chinese history. She said she her mainland schooling taught "a distorted version of history.

"Our generation has suffered great pain and we've paid a huge price, but the way mainlanders forget is very scary. I felt an urgent need to record history," she said.

Editor Wang Ge, also known as Mu Feng, said the topics aimed to clarify issues misunderstood by mainlanders. "We've all been there," Wang said. "We know how mainlanders were taught to believe. We hope the book can highlight those misunderstandings and respond to doubts."

Asked whether they feared the consequences of exposing sensitive information, both Gong and Wang - who live in the United States, but have relatives on the mainland - said it was a price they were willing to pay. "I don't care, and I don't fear [Beijing]," Gong said. "What I care about is whether I am responsible to my child and truthful about history."