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."

Sweden’s right-wing government said on Friday it would seek to tighten gun laws in the wake of the country’s deadliest mass shooting at an adult education center where the attacker appeared to have used several of his own licensed rifles.

A gunman who killed 11 people, including himself, at an adult education centre in central Sweden may have been a student at the school, police said on Thursday, as they described chaotic scenes after the country's deadliest mass shooting as being like an "inferno".

The shooter targeted a center that serves migrants seeking to integrate into a country that had already reversed its liberal migration policies.

A minute's silence was observed across Sweden on Tuesday to honour the victims of a deadly shooting at an adult education centre in the city of Örebro. The minute's silence was held in Örebro and several other Swedish cities at 12 pm (1100 GMT).