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."
The source even went as far as to quote a Chinese official who reportedly said Deng's final words were: "Originally, I did not want to use force."
In fact, Deng died almost 10 years later, in February 1997.
Still, the existence of a separate set of observations helps build a picture of the confusion and anger in China as authorities attempted to arrest and silence student protesters.
Soldiers shot 'at random'
According to one report, a source, whose name has been redacted, claimed members of the "27th Army" shot "'at random at any assembly of persons they encountered' whether demonstrators or not."
Another information report is said to contain details of an exchange between a U.S. source and a female doctor who worked the night shift at Beijing's Capital Hospital on June 4.
The doctor said the hospital's director stepped in to prevent the release of any more bodies after they discovered corpses were being cremated soon after being handed over to the Public Security Bureau, the report said.
Hospital staff then started photographing the dead so they could later be identified. The doctor told the U.S. source, 85% of the hospital's doctors had been trained in the U.S., and they were confident "friends in the U.S." would protect them from persecution by Chinese authorities.
In the same report, the U.S. source said "the real heroes of the massacre were the flatcar pedicab operators who volunteered their services to transport the wounded and dead from Tiananmen Square area to the hospital at the risk of losing heir own lives in the process."
'Very calm in Beijing'
Information filed back to the U.S. also described the atmosphere in Beijing in the months after the crackdown when the city was still under martial law.
"On the surface, Beijing appears very calm," one report said. "Shattered glass windows in buildings have all been replaced, but in the area of the foreign diplomats' apartment houses, one can still see marks on the streets left by tanks."
Standing guard at Tiananmen Square were martial law forces, the report said. The "neatly dressed" troops "looked sharp" and stood at "rigid attention," according to the report, which noted that it was the first time in recent years that the source had "seen such well disciplined People's Liberation Army (PLA) soldiers."
However, outside Tiananmen Square the report said other martial law troops were seen hanging around in groups of three or four "chatting or smoking, slovenly dressed, and appeared to lack discipline."
After the crackdown, China's leaders were said to be on alert for a possible terror attack. One report claimed leaders rarely left their homes and the license plates on their cars were changed "as an added security precaution." The report noted that in the past observers could tell who was at a conference by checking the Mercedes Benz cars parked outside.
There was division, the report claimed, within "the top level of the party" as to whether the search should continue for students who had taken part in the protests. At that stage, the government had "more arrested students than they have prison space," the report said.
Exit checks seemed to have been stepped up at Beijing International Airport, the report claimed, and were "especially strict for any Chinese who happened to look like a student or an intellectual."