About 10 people including the gunman have been killed at an adult education center in what Sweden’s prime minister called the country’s “worst mass shooting.”

The shooting, at a center for adult education in the city of Orebro, was the worst mass shooting in Swedish history, the country’s prime minister said.

Police say around 10 people have been killed in a shooting at an education centre in central Sweden, including the suspected gunman. Prime Minister Ulf Kristersson described Tuesday's attack at Risbergska school in Orebro, 200km (124 miles) west of the capital city Stockholm, as the "worst mass shooting in Swedish history".