Investigators had not uncovered a definitive motive behind the bloodshed by Thursday. Police said there were no warnings beforehand, and they believe the perpetrator acted alone. Authorities said there were no suspected connections to terrorism at this point.

Police said at least 10 people were killed at a school on Tuesday, in what has been described as the worst mass shooting in Sweden’s history. The suspected perpetrator also died.

About 10 people including the gunman have been killed at an adult education center in what Sweden’s prime minister called the country’s “worst mass shooting.”