PORTLAND, Ore. (KOIN) — Officers responded to four shootings in different Portland on Sunday alone, authorities said.

The shootings happened in the Hazelwood, Parkrose and Centennial neighborhoods.

The first shooting was reported around 4 a.m. in the Hazelwood neighborhood near the 13600 block of East Burnside Street; responding officers found one shell casing, but no evidence of any bullet strikes or a victim.

The next shooting happened in the 4600 block of Northeast 102nd Avenue in the Parkrose neighborhood just before 1:30 p.m., when responding officers found a victim who was taken to a local hospital, Portland Police Bureau said. The victim’s current condition is unknown.

Officers in the East Precinct responded to more reported gunfire in Hazelwood just before 9 p.m., which was reported near Southeast 139th Avenue and Southeast Main Street. Officers found at least 21 shell casings, but did not find a victim and did not see noticeable property damage.

Meanwhile, while officers were responding to the second Hazelwood scene, they heard gunfire to the northeast, authorities said. When they responded to the scene in the Centennial neighborhood, authorities say witnesses flagged down officers and reported the shots were fired from a vehicle, which had left the scene. Twelve shell casings were found and officers noted bullets hit a nearby vehicle and building.

Authorities said they did not have “enough certainty” about the vehicle or suspects to release descriptions.

All of the shootings remain under investigation.