They scrambled for cover as quickly as they could as shots rang out, sheltering behind under whatever they could find to escape the gunman and the gore. One survivor with children feared she might never see them again.

OREBRO, Sweden (AP) — Sweden’s worst mass shooting left at least 11 people dead, including the gunman, and at least five seriously wounded at an adult education center west of Stockholm. The gunman’s motive hadn’t been determined by early Wednesday as the Scandinavian nation — where gun violence at schools is very rare — reeled from an attack.

Sweden’s worst mass shooting has left at least 11 people dead, including the gunman, at an adult education center as officials warned that the death toll could rise.

Officials in Sweden have vowed to determine why a man killed 10 people, and apparently himself, in an unprecedented attack that's shaken their "society to its core."

"It is a very painful day for all of Sweden," Prime Minister Ulf Kristersson said in a statement posted on social media.