Swedish police say that a gunman who killed 10 people in the country’s worst mass shooting was connected to the adult education centre where he opened fire with a rifle-like weapon.Authorities said the gunman,

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."

At least 10 people, including the gunman, were killed Tuesday at an adult education center in what Sweden’s prime minister called the country’s worst mass