Last Updated Sep 2, 2019 12:29 PM EDT
Investigators are trying to figure out why a man armed with an assault-style weapon went on a chaotic and deadly shooting rampage in Texas on Saturday. Theacross the heart of Texas oil country. Police say seven people were killed, ranging in age from 15 to 57. At least 22 others were hurt.
The gunman was let go from his job at a trucking company Saturday morning, just hours before the shooting, according to CBS Dallas/Fort Worth. Sources close to the investigation tell the station they "don't believe his firing was the motivation behind the deadly shooting."
Investigators say the rampage began just after 3 p.m. on a west Texas interstate when state troopers tried pulling over a car following reports of a person driving erratically. The driver opened fire with an assault-style rifle — hitting and wounding a trooper — before driving off.
For nearly two hours, the gunman led police on a high-speed chase while firing randomly at people. At one point, he hijacked a mail van, killing 29-year-old Mary Granados, who was working on her postal route.
Mary's twin sister, Rosie, was on the phone with her when the gunman attacked: "She was screaming for help," she said. "And I did my best to go help her, but I couldn't get there on time."
"Did she say anything to you after you heard the screaming?" Begnaud asked.
"No," Granados replied, "because she was already dead."
"I think that he could have taken the car without having to kill her, you know?" she told Begnaud. "He could have taken the car. That's it. That's all he needed. He didn't have to take my sister."
The suspect sped down the highway before slamming into patrol cars in Odessa trying to block the stolen postal service van. The shooter was killed exchanging gunfire with police.
Ethan Baeza was one of dozens of people who ran for safety to a nearby movie theater during the standoff between the shooter and police. "We feared for our lives," Baeza said. "It was the scariest moment of my life."
Investigators say the violence could have been much worse. "Local law enforcement and state troopers pursed him and stopped him from possibly going into a crowded movie theater and having another event of mass violence," said FBI special agent Christopher Combs.
Police have identified the shooter as 36-year-old Seth Ator. They say he acted alone, and don't believe he had any ties to terrorism. Public records show he was arrested in 2001 for criminal trespass and evading arrest, both misdemeanors. It's not clear how Ator got his hands on those weapons. On Sunday, law enforcement were seen searching a home in Odessa believed to be connected to Ator, reports national correspondent David Begnaud.
The shooting occurred less than a month after. It was .
Texas Governor Greg Abbott called the massacres unacceptable. "Too many Texans have lost their lives," Abbott said. "We need solutions that will keep guns out of the hands of criminals, like the killer here in Odessa, while also ensuring that we safeguard second amendment rights."
On Sunday, 10 new laws easing restrictions on guns took effect in Texas.