Members of the police stand guard following a shooting at one of Charles University's buildings in Prague, Czech Republic, Dec 22, 2023. [Reuters]

Czechs mourned the victims of the Czech Republic's worst mass shooting as police tightened security around schools and other public buildings across the country on Friday after authorities said a student gunman killed 14 people at a Prague university building on Thursday.

At the Charles University headquarters, crowds that included Prime Minister Petr Fiala and U.S. Ambassador Bijan Sabet paid tribute to the victims. Some knelt to light candles and lay flowers while others stood crying and hugging each other.

"We are here to show our support as fellow students," said Czech student Daniel Broz. "I was on the other side of the river and hearing gunshots, pops, and not knowing what is going on and then a flurry of police cars passing by was absolutely surreal, especially as a Czech who has never witnessed an event similar to this before."

Charles University canceled all lectures and events on Friday, a day after the shooting in the central European country of 10.9 million where more than 300,000 people own guns, but mass shootings are rare.

The Health Ministry said 27 people were admitted or treated at six Prague hospitals, many with gunshot wounds. Of those, 12 remained in serious condition and at least one in critical condition.

One of the victims died in a hospital.

Authorities began releasing more details about the attack and events that preceded the shooting. They said the 24-year-old student likely shot himself after police cornered him on a balcony and the suspect dropped his long-barrel gun with sights. He carried multiple weapons with him, police said.

"He was left with a shotgun, which does not have long range, and when we were nearing the balcony, he decided to commit suicide," Petr Matejcek, director of the Prague regional police, told a news conference, broadcast live on public television.

The police showed body-camera video footage of special police units storming the university building, searching corridors and rooms and administering first aid to victims. The video also showed police on the roof carrying what appeared to be a body, and later, people leaving the building with hands raised above their heads.

Tracking the suspect

Interior Minister Vit Rakusan called on the media to not give publicity to the gunman or share unverified information.

Police President Martin Vondrasek called the attack the "most shocking experience of my life."

He also said Czech police have been training for an active shooter scenario since the 2011 shootings and a car bomb attack in Norway in which 77 people died.

"That was the year when we realized it can happen anywhere in the world," Vondrasek said.

Leading to Thursday's attack, authorities said the suspect had killed his father at home outside Prague before traveling to the capital.

Police had information from a friend of the shooter that he intended to kill himself and were searching for him at another university building where he was due to attend a lecture.

But he instead went to the main Faculty of Arts building on a busy square across the river from the Prague Castle and just hundreds of meters from the Old Town Square, one of Europe's major tourist attractions.

Police ramp up security

Reporter Jiri Forman, who had learned police were gathering and rushed to the site, helped people flee by yelling at the gunman to distract him on the balcony, evading his fire while also filming the incident and feeding information on the shooter's location to officers.

"Where I stood it was absolutely safe, nobody was there and I knew I could duck behind an obstacle," Forman, who works for a small security-focused news outfit, AKTU.cz, told Reuters.

"The policeman, I believe, shot three times at the attacker. I think this threw him off balance."

Police said they were looking into the gunman's possible connection with a social media account that cited inspiration from a mass shooting in Russia but said on Friday it was not clear if the connection was genuine.

Police ramped up security measures at events and buildings across the country on Friday, saying they had no information on any new threat but "this is a signal we are here and prepared."

Police also said on Friday they found a ballistics match to the weapon used in the shooting death of a young father and his 2-month-old daughter in the woods near a village outside Prague last week in a random attack - a link to the gunman they had suspected.

Police said on Thursday the shooter had a gun license and no criminal record.

The government declared Saturday a national day of mourning.