One person has been killed and several others injured in a sword attack at a high school in central Sweden, authorities said.

Police were called to Brinell School in Fagersta shortly after 14:00 local time on Friday. Officers arrested an 18-year-old man after shooting at the suspect before taking him into custody. His identity has not been released.

Two teenage boys were seriously injured in the attack, while another person suffered minor injuries.

Eight other schools in the area were placed under lockdown following the incident, but those measures have since been lifted. A state of high alert was also declared across the Västmanland region.

Swedish public broadcaster reports said the suspect was wearing a helmet, while local media reported that he was a former student at the school.

Police are investigating the possible motive for the attack and said there is currently no ongoing threat to the public.