Czechs ride a Soviet tank on Wenceslas Square at around 8-9 a.m. on August 21. At this stage, the atmosphere was still relatively relaxed, according to Hajsky. "Lots of people essentially still didn't realize that it was a planned attack," he says. "They thought it was a military exercise or something.... In this photo, you can see that there are kids on the tank. Like they were having a go on a fairground ride."
The lighthearted atmosphere on the streets at this time is evident in the sign saying, "Unauthorized Access Strictly Prohibited," which these young people had commandeered from a nearby building site.
"They rode on the tank employing this typical dark Czech humor," Hajsky says. "People were smiling. At that moment, they still saw it as some sort of spectacle.... But then, of course, things began to go in a different direction..."
According to Hajsky, the Soviet troops were taken aback at the local reaction to their arrival in Prague. "They'd more or less come here on a little break," he says, adding that the way they were riding around on their tanks was more reminiscent of a World War II Victory Day parade than an invasion.
At first, Czechs tried to peaceably remonstrate with the soldiers, but their pleas fell on deaf ears. "They either acted like they couldn't understand or they told us they were coming to our aid," says Hajsky. "They had these slogans like...'You have a counterrevolution going on here! [or] We'll save you from the West and its exploitation!' They were just totally illogical things that you'd smile at normally, except it was no real laughing matter when they began shooting."
A few blocks away from Wenceslas Square, on Vinohradska Street, journalists at Czechoslovak Radio had continued broadcasting news of the invasion, much to the chagrin of the Soviets, who had moved quickly to try and suppress all media outlets. As troops arrived to shut the station down, people came out in their droves to show their support for the broadcasters.
Not long after the previous picture was taken, Hajsky says, the situation around Czechoslovak Radio descended into chaos. "Some lads managed to get a hold of the shovels that they had on the tanks and to pierce the barrels [of fuel]," he says. "And they set them on fire with cloths soaked in diesel. And with the smoke, you can see how the streets darkened like it was nighttime. And then gradually shrapnel started flying as well. There was a terrible panic. People took cover wherever they could -- behind cars, on the ground."
As the tanks started heating up, Hajsky remembers that many Czechs actually tried to warn the invaders. "Suddenly, people started screaming: 'Get out! Get out before anything happens to you!'" he says with a rueful laugh. "That was the genuinely comic power of the situation -- that there was still some empathy for them."
Even amid the mayhem, the people on the streets still had time for "a little bit of Czech black humor," says Hajsky, pointing to the swastika that someone had pointedly etched on the side of the tank in the picture. "The Russians really didn't like that!"
At least 15 people died outside Czechoslovak Radio headquarters that day, five of them when an unmanned truck plowed into the crowd for reasons that are still unclear.
Hajsky was standing just a few meters away from the incident and took this picture. Years later, he found out that the man in the center dressed in red was called Vaclav Sadilek.
When Hajsky attended a public showing of his photos more than two decades later, after the Velvet Revolution, a young man came up and introduced himself, saying he recognized his father in one of the pictures. "He said that for 21 years they had no idea what had happened to him or how it happened," says Hajsky. "He had recognized him there [in the picture]. It was quite an emotional moment."
Altogether, only around a dozen of the photos Hajsky took of the invasion survived. But his recollection of those events is still crystal clear. Despite witnessing some of the worst carnage that occurred that day, he says his worst moment was when he met up with friends later that evening.
"We were a group of about 15-20 people," he says. "We all met up on the evening of the 21st and a deathly silence hung over us -- just 20 people saying nothing and keeping silent. That was a terribly powerful experience. It still moves me to this day."
When tanks rolled into Prague overnight on August 20-21, 1968, photographer Libor Hajsky was only 20 years old. He had just returned from a holiday abroad and the Soviet-led invasion took him by surprise -- along with the rest of the country.