why? that s because the government of course in beijing has spent decade suppressing even the mere existence of the tiananmen square protests. that means no discussion, news coverage and basic references to june 4th, this anniversary date, are scrubbed from the internet. activists try to subvert the restriction by referring to the event as may 35th. it may be hard to appreciate how effective that kind of suppression even is when we get to watch it here from the u.s., a nation with a very free press. but the chinese government s efforts have left many young chinese citizens totally ignorant of a part of their history that the rest of the world knows. that is the subject of a very fascinating new report from our our journalist partners. you know what happened on june 4th, 1989, in china? [ speaking foreign language ]
reporter: 25 years after thousand of chinese students gathered in tiananmen square for an extraordinary show of civil disobedience. in beijing today there is a real sense of historical amnesia. reporter: back then the students demonstration against corruption and inequality and lack of basic political freedom was crushed by the military. and the men who ruled china from the buildings around the famous square also known as the gate of heavenly peace. these days the tanks are replaced by an army of digital sensor whose wipe out any public mention of the tiananmen square crackdown. an incredibly massive
disobedience. in beijing today there is a real sense of historical amnesia. reporter: back then the students demonstration against corruption and inequality and lack of basic political freedom was crushed by the military. and the men who ruled china from the buildings around the famous square also known as the gate of heavenly peace. these days the tanks are replaced by an army of digital sensor whose wipe out any public mention of the tiananmen square crackdown. an incredibly massive undertaking. shaping the minds of a billion people. we have been collecting posts from the chinese version of twitter and tracking the ones mysteriously deleted by state censors and internal units. turns out many of the deleted posts had something to do with commemorating the anniversary of tiananmen square.
today is the 25th year anniversary of the tiananmen square demonstrations. the six-week uprising that began with the sudden death of the reformer and evolved into a broader night for democracy. on june 4, 1989, the chinese government ordered a military crackdown on student protests. images from tiananmen square showed arm troops and tanks and people s liberation army suppressing the movement with a brutal efficiency, even shooting many protesters dead in the street. today in hong kong, thousand held a vigil. hong kong was not part of the mainland in 1989 and still remains a semiautonomous city state. one of the places connected to china where public demonstrations are occurring. why? that s because the government of course in beijing has spent decade suppressing even the mere existence of the tiananmen square protests. that means no discussion, news coverage and basic references to june 4th, this anniversary date, are scrubbed from the internet.
reporter: we learned there was another video. released this year and only seen by the u.s. government. that sparked the greatest concern. an official telling abc news the once fresh-faced soldier was clearly becoming frail and disengaged. that s why there was such urgency going in once the deal was secured according to the official. as for the accusations of desertion, that is a crime punishable by jail time but no officials we are speaking to believe that s on the table given his years of captivity. martha raddatz, abc news, washington. thank you, martha. security is tight in central beijing this morning on the 25th anniversary of the tiananmen square protests. scores of police and para military troops are patrolling the vast plaza as the government tries to head off any demonstrations. access to social media has been restricted or disrupted. hundreds of student protesters were gunned down by the government this week back in 1989.