Hong Kong (CNN) -- Soldiers from outside Beijing called to the Chinese capital to boost troop numbers "were laughing" as they shot randomly at protesters in Tiananmen Square on June 4, 1989, according to declassified U.S. documents. The documents were among 25 Defense Intelligence Agency (DIA) records released to mark 25 years since Chinese authorities sanctioned a brutal crackdown that killed hundreds, if not thousands, of pro-democracy protesters. Each typed report is clearly marked as "not finally evaluated intelligence," and some contain obvious inaccuracies including claims from the U.S. source that Supreme Leader Deng Xiaoping had "died of heart failure."
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U.S. releases classified documents to mark 25 years since Tiananmen crackdown
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25 documents reveal details from June 4, 1989, including observations of troops
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On that day, Chinese troops fired on pro-democracy protesters in Beijing
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Some troops were said to be "laughing" as they shot randomly at students
"On the surface, @placeholder appears very calm," one report said.