NORTH TEXAS (CBSDFW.COM) – Federal agents have not identified where the accused gunman, Patrick Crusius, purchased the weapon he used in deadly attack in El Paso Saturday.

But the El Paso Police Chief said the AK-47-style assault rifle was bought legally.

An ATF spokeswoman said due to the nature of the crime, agents immediately worked to trace the firearm used in the shooting.

Crusius hails from North Texas, but state and local authorities have not released where he purchased the weapon.

An ATF database from Dec. 2017 lists roughly 1,470 licensed federal firearm dealers just in Dallas-Fort Worth.

“We need to see if the system is in operation and where did it break down,” said Oliver ‘Buck’ Revell, a former FBI Special Agent in Charge based in Dallas.

◊ MORE ABOUT EL PASO ATTACK

In Texas, there are few requirements that stand between a gun buyer and a gun.

Potential buyers who are looking to purchase a firearm from a dealer in Texas must be at least 21 years of age without any pending criminal charges.

The background check is processed by the National Instant Criminal Background Check system, which can approve, delay or deny a purchase.

If NICS does not turn up any records and the individual shows no overt signs of mental instability, there’s little a dealer can legally do to stop the sale.

Texas is a “shall issue” state, which means if a buyer meets certain eligibility requirements, including a federal background check, to buy a firearm from a dealer, a permit to carry a concealed weapon shall be issued.

Firearm purchases through a private seller are not subject to a background check.

Investigators said the accused gunman in the deadly Dayton shooting, Connor Betts, also purchased his weapon legally. In fact, police said Betts reportedly bought the firearm online in Texas, along with 100-round drum magazines.

Revell said Texas does not limit the amount of ammunition or the number of firearms a customer can purchase at once.