Norwegian police were alerted shortly after lunch on Monday.
- We are in Ammerud now with great resources. The incident has occurred in Ammerudveien in or near an apartment, says operations manager Gjermund Stokkli to NRK.
A suspected offender in his 30s is arrested, according to the Oslo police on Twitter. There is no reason to believe that there are more perpetrators.
- There are several people injured. So far, police have found three injured, reports NRK.
The extent of the injuries to the three people is unclear. They have been taken to hospitals. According to the police, the deed must have happened in connection with an apartment.
Police say they cannot comment on possible motives, VG states.