Authorities believe Juan David Ortiz’s government-issued handgun may have been used in last month’s serial murders.

Webb County District Attorney Isidro Alaniz reveals why they’re considering this possibility.

“The casings that have been recovered at each crime scene are for 40 calibers. The agents in the service carry 40 calibers. There was one discovered in his truck that we believe will make a match but we will not know until we have the ballistics and scientific study completed.”

Alaniz says he doesn’t believe these murders happened during work hours. He adds they’re trying to put the case together and labels it as complicated.

“There is a lot of evidence that we are trying to study; DNA evidence, evidence taken from the truck, from his home, the telephones. We are trying to tell a story at the time that we go to court from September the 3rd up to the 14th and the morning of the 15th when he was arrested.”

The 35-year-old is accused of killing four victims by shooting them execution-style. He was arrested when one woman escaped and notified authorities. Officials say they might have this case indicted by December 5th. Meanwhile, Ortiz continues behind bars at the Webb County Jail.