Two people were pinned under the car and died at the crash scene, while two others died after being taken to a hospital, police said. Two other people were hospitalized with life-threatening injuries.
The driver also was taken by ambulance to a hospital, police said. Police have not yet released the names of the victims, pending next-of-kin notifications.
Police arrested the 24-year-old driver on charges including four counts of first-degree manslaughter, second-degree assault, third-degree assault and six counts of reckless endangerment, they said in a later news release.
He is being held at the Marion County Jail, police said. It was not immediately clear if he has an attorney.
CNN has reached out to the Marion County District Attorney’s Office for more information.
After the crash, officers helped several uninjured people at the encampment collect their belongings and provided shelter assistance, police said. Three people were taken to a motel, according to the earlier release; the exact number of people and tents at the encampment was not known.
“The City of Salem’s homeless advocacy partners were also contacted in an effort to get the members of our unsheltered community connected to needed resources as a result of this tragedy,” the release said.