PHOENIX (AP) — Two people were killed and eight others critically injured in an early morning crash Saturday on an Arizona highway, authorities said.

The accident occurred about 1 a.m. near Lake Pleasant about 40 miles outside Phoenix when one vehicle attempted to pass another at a high rate of speed, Peoria police spokeswoman Amanda Jacinto said.

A total of 15 people were involved in three vehicles. Two victims died at the scene, while 10 others were transported to area hospitals, eight of them with life-threatening injuries, Jacinto said.

The eight remained in critical condition later Saturday morning.

“Some of them were in the back of a pickup truck riding in the bed,” Jacinto said, adding that they were thrown from the vehicle.

The initial investigation showed others in the vehicles were not wearing seatbelts, she said.

The victims’ identities had not yet been released, but authorities say they are in their late teens or early twenties.

Investigators were probing whether drugs or alcohol played a role in the crash.

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