Two people, including an off-duty officer, were also injured in the Wednesday evening rampage, which the incoming prime minister described as cruel.
After reports streamed in of a man roaming the town center, shooting at people with a bow and arrow, law enforcement officers in Kongsberg, southwest of the capital, arrested a 37-year-old man. He will stand trial after the police, which has said he appeared to be acting alone, charged him on Thursday.
âThe incidents in Kongsberg currently appear to be a terrorist act, but the investigation ⦠will clarify in more detail,â said the security agency, known as PST. Its statement added that the threat level in Norway had not changed and remained moderate.
Regional police chief Ole B. Saeverud told reporters earlier on Thursday that the suspect was a Muslim convert, and that police had received reports in the past flagging he may have been radicalized, although none came this year. He did not elaborate on those concerns.
After the attack, police released some personal details about the suspect because of rumors circulating on social media about possible perpetrators who were not involved.
The confrontation unraveled shortly after 6 p.m. local time in Kongsberg including around a Coop Extra supermarket, according to police and local media. Helicopters, bomb squads and police descended on the town, ordering people to stay inside.
When the first patrol arrived, the alleged attacker tried to target officers with his weapons too before they arrested him about 30 minutes later.
The next morning, many residents were in shock. âI heard a scream I had never heard before,â one of them, Thomas Nilsen, told Norwayâs public broadcaster NRK. âI will never forget it â it sounded like a death cry.â
Norwegian media reported that a court had granted a restraining order last year for the alleged attacker to stay away from two of his family members for six months after he threatened to kill one of them. The police attorney said psychiatric experts would assess him on Thursday and that he had confessed to Wednesdayâs attack.
Police in the Scandinavian country, most of whom are usually unarmed, were temporarily ordered to carry weapons on Wednesday night, the justice minister said.
The killings rocked the town hours before acting prime minister Erna Solberg, who called them âgruesome,â was due to leave office. The incoming prime minister, Jonas Gahr Store, who is taking over on Thursday, said it was âa cruel and brutal act.â
It was the countryâs worst mass killing since 2011, when a right-wing extremist killed 77 people in a bombing and shooting. He was given the maximum jail term of 21 years â but his sentence can be extended indefinitely as long as he is considered a danger to society.