All Swedish schools and pre-schools will have to make plans to keep unauthorised people off their premises, the government said on Wednesday, as the country tries to come to terms with the worst school shooting in its history last week.

Sweden's government said Wednesday it would boost security at schools after the country's worst mass shooting left 10 dead, giving teachers the right to search students' bags among other measures.

A second victim succumbed to their injuries two days after an employee is suspected of opening fire at a warehouse, police say.

Government offices, schools and workplaces fell silent in Sweden at midday on Tuesday in remembrance of the victims of a mass shooting at an adult education centre last week when a gunman killed 10 people before turning his weapon on himself.

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.

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."

Government offices, schools and workplaces fell silent in Sweden at midday on Tuesday in remembrance of the victims of a mass shooting at an adult education centre last week when a gunman killed 10 people before turning his weapon on himself.

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).