BEIJING—The former Chinese leader Deng Xiaoping ordered the military to try to limit injuries when it moved against Tiananmen Square protesters 21 years ago but told it to be ready to “;shed some blood”; if necessary, according to an unpublished diary said to document internal decisions that led to the violent crackdown.

The death toll from the military action against the protesters, which occurred on June 4, 1989, remains in dispute. Official estimates at the time said 200 protesters had died; some rights activists place the toll at 1,000 or more and say 70 to 300 Tiananmen protesters remain in prison.

The diary, covering about nine weeks before and after the military action, is said to have been written by Li Peng, China's prime minister at the time and an ally of conservatives in the Chinese leadership. A Hong Kong publisher, New Century Press, plans to release the 279-page manuscript as a Chinese-language book June 22.

The same publisher caused a sensation in May 2009 by issuing the secret memoirs of Zhao Ziyang, the Chinese Communist Party leader who opposed using force against the Tiananmen protesters and was ousted by his rivals after the military crushed the protests.

Zhao, who spent the rest of his life under house arrest, secretly recorded his memoirs on cassettes that were later smuggled out of China. Li, who is today a retired but influential party elder, was said to have wanted to publish his work in 2004, on the 15th anniversary of the Tiananmen protests, but was discouraged by Chinese leaders.

Bao Pu, the Hong Kong publisher of both works, said in a telephone interview Friday that he had received the diary attributed to Li from an unidentified source and so could not guarantee its authenticity. The diary and 34 accompanying photographs appeared to have been photocopied from a printer's galley, he said.

Bao said he was unable to contact Li, now 81 and reportedly in ill health, to verify the contents. But he said a detailed study of the work convinced him and other experts that Li was the author. A Hong Kong magazine, Asia Weekly, reported the existence of a Li Peng memoir with identical details in 2004, one year after Li retired from his last official posts.

“;I still think it's real, and it's really presentable,”; Bao said.

A complete copy of the manuscript was not immediately available. But The South China Morning Post, based in Hong Kong, which reported Friday that it had obtained a copy of the manuscript, said Li wrote in a foreword dated Dec. 6, 2003, that he felt bound to record what had happened “;to serve as the most important historical testimony”; about Tiananmen.

The diary appears to hold no major surprises. Deng publicly supported military action to end the protests at the time. But it provides a glimpse of the thinking of one of the leaders at the center of the decision-making.

The newspaper said Li wrote that the protesters had threatened to send China into a new era of political upheaval akin to the chaos into which Mao periodically plunged the nation.

“;From the beginning of the turmoil, I have prepared for the worst,”; the newspaper wrote, quoting an entry dated May 2, 1989. “;I would rather sacrifice my own life and that of my family to prevent China from going through a tragedy like the Cultural Revolution.”;

That comparison ignores the fact that the Cultural Revolution was orchestrated by Mao to undermine rival leaders he felt were insufficiently devoted to his revolutionary agenda. The analysis attributed to Li is also at odds with that of Zhao, who contended that the students wanted reform, not revolution. In the diary, the newspaper reported, Li states that he began to take issue with Zhao days after the protests began in April 1989.

But according to a prologue by Wu Guoguang, a scholar at the University of Victoria in British Columbia, the diary makes clear that Deng, not Li, led the drive to crush the demonstrations and oust Zhao.

“;This book has clearly revealed that Deng was the proposer and decision maker of enacting martial law in parts of Beijing in 1989,”; Wu wrote. “;And he gave the final approval to the 'ground clearing' operation in Tiananmen Square on June 3.”;

Deng, who died in 1997, never detailed his role in the decision-making in 1989. Other historical accounts have said that he, Li and several other hard-line leaders pressed for tougher action to put down the protests.

Bao Tong, a senior aide to Zhao who was imprisoned after the Tiananmen protests, said Friday that he welcomed publication of the diary, although Li's view of the crisis was at sharp odds with his own.

“;There's an old saying in China: If you hear widely from all the sources, your doubts of the situation will very soon clear up,”; he said.

Most Chinese will not have that opportunity because Zhao's memoir is not legally available on the mainland, and the diary attributed to Li also seems certain to be banned. “;But the world has entered into an era of information,”; said Bao, the father of Bao Pu, “;and with the spread of the Internet, there can be no monopoly on the truth.”;

Li Bibo contributed research.