A lone gunman opened fire in a university building in Prague, killing at least 15 people and injuring more than 20.

The incident is the worst mass shooting in the Czech Republic and was confirmed by the Police and the City’s Rescue Service.

The bloodshed took place in the philosophy department building of Charles University, where the shooter was a student. Reports say the gunman was also killed.

Prague’s Police Chief Martin Vondrasek said 24 people were injured, but with a warning that the death toll could rise.