Niclas Hallgren, the deputy regional police chief for Bergslagen, told SVT: “Most of the victims in the school shooting had a foreign background. Ethnicity is a circumstance that the police have taken into account since early in the investigation when assessing a possible motive.” He added: “It is too early to say that there is a specific reason behind the act.”
It was originally published by TV4, but it is not solid evidence. I believe Omni has also shared reporting on it as well. “Ni ska bort från Europa” is the phrase that may have been said by an unknown person.