Badly wounded, Salim Karim Iskef managed to video-call his fiancée to say he loved her one last time before he died in Sweden's deadliest mass shooting.

A gunman opened fire at an adult education center in the Swedish city of Örebro on Tuesday, killing at least 10 people in what the country’s prime minister called the “worst mass shooting in Swedish history.

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."