PRAGUE — The Czech Republic came to a standstill at noon Saturday as people across the country observed a minute of silence as part of a national day of mourning to honor the victims of the worst mass killing in Czech history.

National flags on public buildings were at half-staff and bells tolled at noon. A Mass at St. Vitus cathedral in Prague, the biggest in the country, was celebrated for the victims. President Petr Pavel and speakers of both houses of Parliament attended the service that was open to everyone.

“We’re all still in a shock in our own ways,” Prague archbishop Jan Graubner said. “We need to clearly condemn what happened but we also need to look into the future.”

“Nobody should be left alone in these tough moments,” Charles University rector Milena Kralickova said in her remarks toward the end of the Mass. The shooting inside the university’s Faculty of Arts on Thursday killed 14 people.

Similar religious services were held in other cities and towns, while Christmas markets in a number of places were closed or reduced their programs amid boosted security measures.

The shooting in the university at the heart of the Czech capital also wounded 25 people before the gunman killed himself. Police and prosecutors said they have evidence the 24-year-old shooter also killed his father earlier in the day and a man and a baby in Prague last week.

A sea of candles was shining at an impromptu memorial for the victims created in front of the university headquarters.

“It’s been a horrible experience for us all but it still can’t be compared with what the victims had to experience at the time of the attack and what their dear ones have to experience now,” said Milos Vystrcil, speaker of Parliament’s upper house, the Senate, one of those who came to light a candle.

“I think that to help them at this point we express our support and that’s what we’re all doing now.”

The names of the 14 people who died are slowly being released. The university confirmed two staff members were among them, including the head of the Institute of Music Sciences, Lenka Hlávková. First-year student Lucie Spindlerova was another, said the Lidove noviny daily, where she also worked.

The shooter was Czech and a student at the Faculty of Arts. Investigators do not suspect a link to any extremist ideology or groups. Officials said they believed he acted alone. His motive is not yet clear.

Previously, the nation’s worst mass shooting was in 2015, when a gunman opened fire in the southeastern town of Uhersky Brod, killing eight before fatally shooting himself.