One person has been killed in a sword attack at a high school in central Sweden, authorities have said.

Police were called to the Brinell School in Fagersta shortly after 14:00 local time (13:00 BST) on Friday, where officers arrested an 18-year-old man.

In an update on Friday, police said officers fired at the suspect before arresting and detaining him. He has not been named.

Two teenage boys were seriously injured in the attack. Another person had minor injuries.

Eight other schools in the area were placed under lockdown measures – which have now been lifted – while a state of high alert was declared in the Västmanland region following the attack.

Sweden’s public broadcaster reported that the suspect was wearing a helmet. Local media also said he was a former student.

Police said officers were now working to establish possible motives, adding that there was currently no danger to the public.

In a post on X, Sweden’s Prime Minsiter Ulf Kristersson described the attack as a “serious incident,” and said “we do not know what lies behind the act, but we know that police are working very intensively”.

Sweden’s King Carl XVI Gustaf said he received the news “with dismay and sadness”.

In a statement, he said: “My thoughts are with those directly affected, as well as their families and loved ones.”

Students at Brinell School had only just returned to the classroom following the summer break, with the new term beginning either on Monday or Wednesday this week, depending on the academic year.

The school has just under 500 students on its roster, according to SVT, and is located 170km (105 miles) north-west of the capital, Stockholm.

Sweden has experienced a number of attacks on educational institutions in recent years.

The country experienced its worst-ever mass shooting in 2025, where 11 people, including the gunman, died at an adult education centre in Örebro.

This led to the government tightening the country’s gun laws after it was found that the suspect legally owned four rifles, three of which were found in the school where attack took place.

Two teachers were killed in a violent attack on a secondary school in Malmo in 2022 – an 18-year-old student later confessed to the attack.

In 2015, a teacher and a pupil were killed in a sword attack at a school in Trollhättan.