Here is more from the article cited by the OP.
Someone in the protest group allegedly returned fire, striking Smith. That person has not been identified. According to the Portland Police Bureau (PPB), Smith remains in the hospital "in serious condition." He has not been charged with any crime, more than 48 hours after the mass shooting took place.
PPB has shared little information about the incident. Much of what the bureau has made public appears to be inaccurate. In a press release sent Sunday afternoon, PPB reported that the Saturday incident started with a "confrontation between an armed homeowner and armed protesters." Smith does not own the apartment complex he lives in, and it appears he was the sole individual who initiated the confrontation.
PPB has also refused to explain whether anyone has been arrested in relation to the shooting. Asked to clarify this position, PPB spokesperson Nathan Sheppard said that the reasoning is "complicated."
"Unfortunately, not all cases are simple," Sheppard wrote in an email to the Mercury. "In some, a determination has to be made of who is a suspect and who is a victim. Cases can be fluid, and as additional facts are learned, who is a victim and who is a suspect can also change."
"Unfortunately, not all cases are simple. . . " Well, damn, boy -- this one is simple: Rightwing dimwit shot up peaceful demonstrators, someone in the crowd of demonstrators was packing heat and stood his/her ground. Case closed. Maybe the next would-be shooter will think twice.