Survivors of Sweden's worst mass shooting on Wednesday recalled trying to save the lives of their comrades at a school for adults in Örebro, a day after a gunman killed 11 people on what the prime minister called a "dark day" in the country's history.

Swedish police are still investigating the gunman's personal history and have not said the attack, which killed 11 people, was targeted. Hellen Werme, a 35-year-old trainee nurse, survived the shooting. She and her classmates locked themselves inside their classroom as the shooter prowled the corridors.

The king and queen visited the scene of the tragic event that occurred on Tuesday and Swedish flags were flown at half-mast to honor the victims.