Czech students clung to the side of their university building on Thursday as their fellow student massacred at least 16 people in the worst mass murder in Europe since the 2015 Paris terror attacks.

The gunman, who studied Polish history at Charles University in Prague, first murdered his father and then shot his fellow students. Another 24 people were injured during his rampage; the rampage only ended when he himself was “eliminated”.

Images show the lone gunman, identified by local media as David Kozák, aiming a black rifle at the campus, which is located near the tourist attraction in the old town of the Czech capital.

Police believe 24-year-old Kozák shot himself after an exchange of gunfire with police officers on the sidewalk of the building. He may have been injured in the process. An autopsy is pending, but police said the “devastating injuries” suggest suicide.

Prime Minister Petr Fiala said he had cancelled a trip to the east of the country because of “the tragic events at the Faculty of Philosophy” and was returning to Prague, while the city’s mayor, Bohuslav Svoboda, said he was “completely shocked”.

European leaders sent their condolences. “We are shocked by the senseless violence of the shooting that claimed several lives in Prague today,” European Commission President Ursula von der Leyen said on X. “We stand and mourn with you.”

Dutch Prime Minister Mark Rutte said his thoughts were “with the victims and their relatives”, while Hungarian Prime Minister Viktor Orban said he was “deeply shocked by the heinous shooting at Charles University”.

Teachers and students were instructed by email to seek shelter during the police operation. “Stay where you are and do not go anywhere. If you are in the offices, lock them, move furniture in front of the door and turn off the lights,” the email said.