The bloodshed took place in the philosophy department building of Charles University, where the shooter was a student, Prague Police Chief Martin Vondrasek said. The gunman also died, authorities said. His name has not been released.

Vondrasek said in the evening that 14 people had died and 25 were injured, after earlier reporting that 15 had died and 24 were hurt. He didn't explain the change. Authorities warned that the death toll could rise.

Police gave no details about the victims or a possible motive for the shooting at the building located near the Vltava River in Jan Palach Square. Czech Interior Minister Vit Rakusan said investigators do not suspect a link to any extremist ideology or groups.

Vondrasek said police believe the gunman killed his father earlier Thursday in his hometown of Hostoun, just west of Prague, and that he had also been planning to kill himself. He didn't elaborate.

Later Thursday, Vondrasek said that based on a search of his home, the gunman was also suspected in the killing of another man and his 2-month-old daughter Dec. 15, in Prague.

The chief described the shooter as an excellent student with no criminal record, but didn't provide any other information.

The gunman suffered "devastating injuries" but it wasn't clear if he killed himself or was shot to death in an exchange of gunfire with officers, Vondrasek said, adding that there was "nothing to suggest that he had an accomplice."

The shooter legally owned several guns — police said he was heavily armed Thursday and was carrying a lot of ammunition — and that what he did was "well thought out, a horrible act," Vondrasek said.

University authorities said they would tighten security in university buildings with immediate effect.

"We mourn the loss of life of members of our university community, express our deepest condolences to all the bereaved and our thoughts are with all those affected by the tragedy," Charles University said in a statement.