Norwegian police said on Monday they had arrested a suspected shooter after receiving reports of gunfire at Oslo's largest shopping centre.
Police said in a statement that no injured people had been found and that it was safe to reopen the centre again, after it was earlier evacuated.
"As of now, it appears that there was only one perpetrator involved," the statement said.
Police spokesperson Tomm Berger told journalists the suspect, a 19 year-old, had called the police before he fired a single shot with a shotgun into the ceiling. The suspect had also been carrying a baseball bat and a knife.

Trump says Iran ceasefire 'on life support' after he rejects Tehran's response
India's Modi to begin five-nation tour, including UAE
EU ministers agree on sanctions targeting violent West Bank settlers
Last six passengers leave Hantavirus-hit ship as captain hails their patience
Suspect in Trump attempted assassination pleads not guilty
UK's Starmer promises to be bolder to try to rescue his job
Philippine lawmakers to vote on impeachment of presidential hopeful Duterte
Six people found dead in boxcar in Texas, police say
