At least five people are dead after a gunman shot more than 20 people as he fled from police before being killed outside a cinema.
The shooting rampage began after the man was stopped at traffic lights by Texas state troopers for failing to signal a left turn.
He then hijacked a postal service vehicle and fired at random as he drove between Odessa and Midland, police said.
The two cities are in the heart of Texas oil country more than 300 miles west of Dallas.
Police initially reported possible multiple shooters, but Odessa police chief Michael Gerke later said there was only one male suspect in his thirties.
The suspect shot at innocent civilians all over Odessa, according to a statement from Odessa police which did not name the man or offer a motive.
The terrifying chain of events began when state troopers tried pulling over a gold car on Interstate 20 for failing to signal a left turn.
Before the vehicle came to a complete stop, the driver pointed a rifle towards the rear window of his car and fired several shots towards the patrol car stopping him, Texas Department of Public Safety spokeswoman Katherine Cesinger said.
The gunshots struck one of two troopers inside the patrol car after which the gunman fled and continued shooting.
Two other police officers were shot before the suspect was killed. The condition of the three officers injured was not immediately released.
Mr Gerke said there were at least 21 injured members of the public.
He said at least five people died.
Mr Gerke did not say whether the gunman was included among the five dead and it was not clear whether he was including the five among the at least 21 civilian shooting victims.
Witness Shauna Saxton was driving with her husband and grandson in Odessa and had paused at traffic lights when they heard loud pops.
Sobbing, she said: I looked over my shoulder to the left and the gold car pulled up and the man was there and he had a very large gun and it was pointing at me.
I started honking my horn. I started swerving and we got a little ahead of him and then for whatever reason the cars in front of me kind of parted.
She said she heard three more shots as she sped away.
The cinema where the suspect was killed is more than 10 miles from where state troopers originally pulled him over.