CNN  — 

Alcohol “may have been a contributing factor” in a crash that saw a motorist drive into an encampment of unhoused people in Salem, Oregon, Sunday morning, killing four, police say.

A preliminary investigation suggests the driver plowed into the encampment after veering off the road, the Salem Police Traffic Team said in a news release Sunday night.

Two people were pinned under the car and died at the scene of the crash, which occurred around 2 a.m. local time, while two others died after being taken to a hospital, police said. Two other people were also hospitalized with life-threatening injuries.

The driver of the vehicle was also taken by ambulance to a hospital, police said.

“No arrests have been made at this point; however, the Salem Police Traffic Team is actively investigating the circumstances and believe alcohol may have been a contributing factor,” police said in the release.

Police have not released the names of the victims, pending next of kin notifications.

Officers helped several uninjured campers collect their belongings and “provided shelter assistance” after the crash, police said. Three people were taken to a local hotel, according to the release, with the exact number of people and tents at the encampment unknown.

“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 this tragedy,” the release said.

The incident remains under investigation.

CNN’s Hannah Sarisohn and Susannah Cullinane contributed to this report.