The gunman in Saturday afternoon’s shooting rampage in West Texas was acting alone when he killed seven people with an “AR-type weapon,” investigators said Sunday.

Those who were killed ranged in age from 15 to 57, Odessa Police Chief Michael Gerke said, suggesting more people could have died had police not killed the gunman outside a crowded movie theater. Two of the victims died overnight.

“He showed up at a movie theater which would tend to show his motive,” Gerke said at a news conference.

The police chief said he wasn’t naming the shooter, described by officials Saturday as a white man in his 30s, because “I refuse to.”

Odessa and Midland police and sheriff's deputies surrounding the area behind the Cinergy movie theater in Odessa, Texas, on Saturday. (Tim Fischer/Midland Reporter-Telegram via AP)

TEXAS SHOOTING LEAVES 7 DEAD, 19 INJURED; SUSPECT DEAD

“I’m not going to give him any notoriety for what he did,” the chief said.

The shooting rampage in Odessa and Midland left 22 others injured, including three law enforcement officers and a 17-month-old girl.

Gerke said no motive has been established for the shooting which began shortly after 3 p.m.

FBI Special Agent in Charge Christopher Combs said the killer had no apparent connection to terror groups. Investigators said the gunman had a criminal record but did not divulge details.

President Trump on Sunday tweeted, "Great job by Texas Law Enforcement and First Responders in handling the terrible shooting tragedy."

The shooting began after Texas state troopers pulled over the gunman for making a left-handed turn without signaling.

Police officers guarding a street in Odessa, Texas, on Saturday. (Dustin Fawcett via AP)

In the chaos that followed, the suspect hijacked a mail carrier truck and fired at random, investigators said.

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Gerke said 15 separate locations had been designated crime scenes.

Texas Department of Public Safety spokeswoman Katherine Cesinger said the driver "pointed a rifle toward the rear window of his car and fired several shots" at the troopers as he was still moving.

The gunshots struck one of two troopers inside the patrol car, Cesinger said, after which the gunman took off and continued shooting.

Two other police officers were shot before the suspect was killed. Investigators said the trooper was in serious but stable condition on Saturday, and the other officers were stable.

Shauna Saxton said she was driving with her husband and grandson in Odessa and had paused at a stoplight when they heard loud pops.

"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," she told TV station KOSA.

Saxton said she was trapped because there were two cars in front of her. "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, sobbing. She said she heard three more shots as she sped away.

The shooting was the second mass shooting in Texas in a month. A gunman killed 22 people in El Paso Aug. 3.

“I have been to too many of these events,” Texas Gov. Greg Abbott said at the news conference.

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He said newly enacted laws would make schools safer from shooting attacks.

The Associated Press contributed to this report.