The man suspected of killing five people in Norway with a bow and arrow has been named as Espen Andersen Braathen.
Police had concerns about signs of radicalization and said the attack appears to have been an 'act of terror'.
A senior officer on Thursday (October 14) said the suspect is a Danish convert to Islam.
"As previously announced, the suspect is a 37-year-old Danish national residing in Norway. Police have previously been in contact with the man in relation to trouble connected to radicalization. We haven't registered anything in regards to him in 2021, but previously."
Flags flew at half-mast across Kongsberg where four women and a man were murdered.
They were all aged between 50 and 70.
Three people were also wounded in the attack on Wednesday evening.
Police said the 37 year-old suspect was in custody and is believed to have acted alone.
A relative of the suspect, who spoke on condition of anonymity to a Danish newspaper, described him as mentally ill and said the family had suffered threats for several years.
The suspect's lawyer told public broadcaster NRK he was cooperating and giving detailed statements regarding the incident.
The attack happened over a 'large area' of Kongsberg - a town of about 28,000 people in southeast Norway.
The death toll was the worst of any attack in Norway since 2011, when a far-right extremist killed 77 people.