The gunman who killed seven people and wounded more than 20 others in a shootout around Odessa, Texas, bought his gun from a private seller. This transaction does not require a personal background check, law enforcement officials told NBC News.
Investigators are now looking into who sold the gun to Seth Ator, 36, who failed a gun background check in 2014 because law enforcement officials had told NBC News that he had a disqualifying mental health problem.
If the person who sold the gun to Ator was aware of his mental health problems, this seller could be the subject of criminal prosecution.
In February, the House passed a bill requiring background checks on almost all private sales, with the exception of those involving family members. But the Senate will not act until President Donald Trump has made his position clear.
Ator had been fired by his employer, Journey Oil Field Services, on Saturday just before he was unleashed in the neighboring towns of Odessa and Midland.
He was killed during a shootout with the police.
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Mass shooting in Odessa, Texas
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Texas Governor Greg Abbott makes gestures at a press conference regarding Saturday's shooting on Sunday, Sept. 1, 2019, in Odessa, Texas. From left to right, Christopher Combs, FBI Special Agent, San Antonio, Odessa Police Chief, Michael Gerke, and Abbott. (AP Photo / Sue Ogrocki)
Odessa police chief, Michael Gerke, announced that he would not pronounce the name of Saturday's shooter during a shootout at a press conference on Sunday 1st September 2019 in Odessa, Texas. (AP Photo / Sue Ogrocki)
Odessa Police chief, Michael Gerke, in the center, answers a question regarding the Saturday shootout at a press conference on Sunday, Sept. 1, 2019 in Odessa, Texas. From left to right, Christopher Combs, FBI Special Agent, San Antonio, Gerke, and Texas Governor Greg Abbott. (AP Photo / Sue Ogrocki)
The Texas governor, Greg Abbott, right, pats Odessa police chief, Michael Gerke, left, at the shoulder during a press conference about the shooting of Saturday, September 1, 2019 in Odessa, Texas. (AP Photo / Sue Ogrocki)
Law enforcement officials are dealing with a scene involved in Saturday's shooting on Sunday, Sept. 1, 2019, in Odessa, Texas. Shots shot out on Sunday in western Texas as authorities investigated why a man was arrested by state soldiers for not reporting the left-hand bend. opened fire on them and escaped, shooting over a dozen people while he was driving before being killed by police outside a movie theater . (AP Photo / Sue Ogrocki)
A police car from the city of Odessa, left, and an American mail car, right, involved in Saturday's shooting, are photographed in front of the Cinergy entertainment center, on Sunday, September 1, 2019 in Odessa, in Texas. Shots have mushroomed in West Texas as authorities have investigated why a man arrested by state soldiers for not reporting the left turn has opened. the fire and escaped, firing on a dozen people while he was driving before being killed by officers in front of a movie theater. (AP Photo / Sue Ogrocki)
A US courier vehicle, on the right, involved in Saturday's shootings, is photographed in front of the Cinergy Entertainment Center on Sunday, Sept. 1, 2019 in Odessa, Texas. Shots have mushroomed in West Texas as authorities have investigated why a man arrested by state soldiers for not reporting the left turn has opened. the fire and escaped, firing on a dozen people while he was driving before being killed by officers in front of a movie theater. A police vehicle is partially blocked to the left. (AP Photo / Sue Ogrocki)
Buying and selling agents in Odessa, Texas, as of August 31, 2019, comments on what is a safety index for the postal service and postal security are also available instead of 20, separating authorizations. (Mark Rogers / American Odessa by AP)
An emergency medical and medical reception at the hospital in Odessa, Texas on August 31, 2019 and a departure day in the Odessa and Midland region, in the region of Texas. (Mark Rogers / American Odessa via AP)
Chief of Odessa Police, Michael Gerke, talks with the media at the Odessa Police Department in Odessa, Texas, on Saturday, August 31, 2019, after a few days later. Man was shot at random in the Odessa and Midland regions. Several people died after an armed man who hijacked a postal service vehicle in western Texas shot dead more than 20 people, authorities said Saturday. The gunman was killed and some policemen were injured. (Mark Rogers / American Odessa via AP)
ODESSA, TX – SEPTEMBER 1: A damaged police vehicle and a US Post Office van blocked by a tape near the location where an armed gunman was shot dead at the Cinergy Odessa cinema following a deadly shooting on 1 January September 2019 in Odessa, Texas. Seven people were killed, in addition to the shooter, and at least 21 others were wounded, including three law enforcement officers after the passage of an armed man. The man who was not identified fled the state soldiers who had tried to shoot him. The gunman then hijacked a vans from the United States and fired indiscriminately with a rifle at people before the authorities shot him and killed him in front of a cinema in Odessa. (Photo by Cengiz Yar / Getty Images)
ODESSA, TX – SEPTEMBER 1: A damaged police vehicle and a US Post Office van blocked by a tape near the location where an armed gunman was shot dead at the Cinergy Odessa cinema following a deadly shooting on 1 January September 2019 in Odessa, Texas. Seven people were killed, in addition to the shooter, and at least 21 others were wounded, including three law enforcement officers after the passage of an armed man. The man who was not identified fled the state soldiers who had tried to shoot him. The gunman then hijacked a vans from the United States and fired indiscriminately with a rifle at people before the authorities shot him and killed him in front of a cinema in Odessa. (Photo by Cengiz Yar / Getty Images)
ODESSA, TX – SEPTEMBER 1: A damaged police vehicle and a US Post Office van blocked by a tape near the location where an armed gunman was shot dead at the Cinergy Odessa cinema following a deadly shooting on 1 January September 2019 in Odessa, Texas. Seven people were killed, in addition to the shooter, and at least 21 others were wounded, including three law enforcement officers after the passage of an armed man. The man who was not identified fled the state soldiers who had tried to shoot him. The gunman then hijacked a vans from the United States and fired indiscriminately with a rifle at people before the authorities shot him and killed him in front of a cinema in Odessa. (Photo by Cengiz Yar / Getty Images)
ODESSA, TX – SEPTEMBER 1: Texas Gov. Greg Abbott gives a press conference to local and federal law enforcement officials at the University of Texas Permian Basin (UTPB) as a result of A murderous shootout on September 1, 2019 in Odessa, Texas. Seven people were killed, in addition to the shooter, and at least 21 others were wounded, including three law enforcement officers after the passage of an armed man. The man who was not identified fled the state soldiers who had tried to shoot him. The gunman then hijacked a vans from the United States and fired indiscriminately with a rifle at people before the authorities shot him and killed him in front of a cinema in Odessa. (Photo by Cengiz Yar / Getty Images)
ODESSA, TX – SEPTEMBER 1: Texas Governor Greg Abbott holds a press conference with local and federal law enforcement officials at the University of Texas Permian Basin (UTPB) as a result of A deadly shootout on September 1, 2019 in Odessa, Texas. Seven people were killed, in addition to the shooter, and at least 21 others were wounded, including three law enforcement officers after the passage of an armed man. The man who was not identified fled the state soldiers who had tried to shoot him. The gunman then hijacked a vans from the United States and fired indiscriminately with a rifle at people before the authorities shot him and killed him in front of a cinema in Odessa. (Photo by Cengiz Yar / Getty Images)
ODESSA, TX – SEPTEMBER 1: Texas Governor Greg Abbott holds a press conference with local and federal law enforcement officials at the University of Texas Permian Basin (UTPB) as a result of A deadly shootout on September 1, 2019 in Odessa, Texas. Seven people were killed, in addition to the shooter, and at least 21 others were wounded, including three law enforcement officers after the passage of an armed man. The man who was not identified fled the state soldiers who had tried to shoot him. The gunman then hijacked a vans from the United States and fired indiscriminately with a rifle at people before the authorities shot him and killed him in front of a cinema in Odessa. (Photo by Cengiz Yar / Getty Images)
ODESSA, TX – SEPTEMBER 1: Flowers are hung on a sign from the Odessa Police Department as a result of a deadly shootout on September 1, 2019 in Odessa, Texas. Seven people were killed, in addition to the shooter, and at least 21 others were wounded, including three law enforcement officers after the passage of an armed man. The man who was not identified fled the state soldiers who had tried to shoot him. The gunman then hijacked a vans from the United States and fired indiscriminately with a rifle at people before the authorities shot him and killed him in front of a cinema in Odessa. (Photo by Cengiz Yar / Getty Images)
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