Danish police said Monday that the 22-year-old suspect in a weekend shooting at a Copenhagen mall that left three dead was known to mental health services.
"Our suspect is also known among psychiatric services, beyond that I do not wish to comment," Copenhagen police chief Soren Thomassen told a press conference.
Thomassen added that the victims appeared to have been randomly targeted and there was nothing to indicate it was an act of terror.
Police have said they believe videos of the suspect circulating since Sunday evening on social media to be authentic.
The young man can be seen posing with weapons, mimicking suicide gestures and talking about psychiatric medication "that does not work".
YouTube and Instagram accounts believed to belong to the suspect were closed overnight, AFP noted.
The three killed have been identified as a Danish woman and man, both aged 17, and a 47-year-old Russian citizen residing in Denmark.
Another four were injured in the shooting: two Danish women, aged 19 and 40, and two Swedish citizens, a 50-year-old man and a 16-year-old woman.
The shooting occurred Sunday afternoon at the busy Fields shopping mall, located between the city centre and Copenhagen airport.