Authorities stated the suspect, Seth Ator, was considered a "prohibited person" barred by law from purchasing or possessing a firearm because he was diagnosed as being mentally ill. It was further confirmed by Texas Gov. Greg Abbott, who said the shooter failed a background check.
According to federal and state sources, the private sale law allows the sale or purchase of handguns and rifles, including the semi-automatic AR-15 assault style rifles.
The seller may not sell a weapon if he or she knows the buyer is flagged, but is under no obligation to do a background check or ask about the buyer's status.
Odessa Police Chief Michael Gerke said Ator had been fired Saturday from Journey Oilfield Services. He said both Ator and the company called 911 after the firing, but that Ator was gone by the time police showed up. FBI special agent Christopher Combs says Ator's statements on the phone were "rambling."
SEE ALSO: Odessa gunman called FBI before deadly shooting began
Authorities said Ator killed seven people and injured at least 23 others Saturday before officers killed him outside a busy movie theater in Odessa.
Combs said Ator "was on a long spiral down" before the shooting and that he went to work that day "in trouble."
Online court records show Ator was arrested in 2001 for a misdemeanor offense that would not have prevented him from legally purchasing firearms in Texas.
Authorities said those killed were between 15 and 57 years old.
The Associated Press contributed to this report.
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