A driver told Tulsa Police the rising sun blinded him as he turned left into the path of an eastbound SUV on 46th Street North Thursday morning.
The resulting crash sent the car off the road.
The driver said he realized he had forgotten to lock a door at work and was turning around to go back and lock it when the crash happened.
Firefighters from the Tulsa and Limestone departments had to free the driver from the car.
Another driver who was slowing down for that crash was struck by a car going in the opposite direction which had swerved to miss the first crash.
At least two people were sent to Tulsa hospitals because of their injuries.
Tulsa Police say the two crashes closed 46th Street North near 129th East Avenue for about an hour as crews cleaned up the wreckage.