Wednesday's shooting at Campus Risbergska, a school for young adults in Orebro, was Sweden's worst massacre.

"We have found several weapons," the spokesman told AFP, specifying that they were long-barrelled weapons, "meaning rifles."

The suspected gunman, identified by the Swedish press as 35-year-old Rickard Andersson, had gun licenses for four weapons, according to media reports.

Police have not named the suspect and said they are still working to establish a reason for the killing spree, just adding that the shooter was "obviously motivated and had access to firearms".

Asked about reports that the gunman turned his gun on himself, Orebro police chief Roberto Eid Forest told reporters Wednesday: "There is a lot to indicate that."

Swedish media reports suggested the killer was a 35-year-old local man who had been living as a recluse and suffering from psychological problems.

According to Aftonbladet newspaper, he reportedly hid his weapons in a guitar case and changed into military style garb in a bathroom, before opening fire.

Broadcaster TV4 published a video filmed by a student hiding in a bathroom in which shots can be heard outside and a person can be heard shouting: "You will leave Europe!"

The broadcaster noted that the education centre also housed Swedish classes for immigrants.

Police a scheduled to give another press conference at 10:00 am local time (0900 GMT).