The student who shot two people at a Maryland school on Tuesday was legally prohibited from possessing or owning the firearm he used.

The shooter, identified as 17-year-old Austin Rollins, was well below Maryland’s 21-year age requirement to purchase or possess a handgun. Nonetheless, he reportedly used a 9 mm Glock to carry out the shooting.

Law enforcement officials say they are tracing the gun to determine its owner, reports the Baltimore Sun.

Rollins allegedly shot two of his classmates before he was killed, although it is still unclear if he killed himself or was shot by a school resource officer. A 14-year-old boy who was shot is in “good condition,” while a 16-year-old girl is stable. (RELATED: Armed School Resource Officer Engages Maryland High School Shooter)

After the Parkland, Florida school shooting last month, a number of gun retailers, including Walmart and Dick’s Sporting Goods, limited the sale of rifles to those 21 years and older in the hope of preventing similar shootings. Federal law currently requires people to be at least 18 years old to purchase a long gun and at least 21 years to purchase a handgun.

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