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."

Everything we know so far about campus attack which left 11 dead - Sweden’s prime minister said the attack at the Risbergska School was the worst mass shooting in country’s history

One day after the killings at an adult educational center, some gathered to lay flowers and come to grips with the violence.