TUCSON, Ariz. (AP) — An April trial date has been scheduled for an Internal Revenue Service special agent accused of involuntary manslaughter in the shooting death of a fellow employee after training exercises at a firearm range last year.

A federal grand jury indicted Larry Edward Brown Jr. on one count of involuntary manslaughter of an officer of the United States on Wednesday. He was released Friday after his initial court appearance in Tucson. An April 2 trial is scheduled.

The 42-year-old Brown, of the Phoenix suburb of Peoria, is charged in the Aug. 17 shooting of IRS Special Agent Patrick Bauer.

The U.S. Attorney’s Office said both Brown and Bauer were trained use-of-force instructors and special agents of the IRS’ Criminal Investigation unit. Bauer was a 15-year veteran and Brown has more than 12 years of experience.

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Prosecutors said the special agents were using the range at the Federal Correctional Institution in Phoenix for standard pistol qualifications and classroom training.

They said training had concluded for the day when Brown entered a building where firearms instructors can observe and command live-fire training.

According to the indictment, Bauer had led the live-fire pistol qualifications and Brown “handled his firearm without due caution and with reckless disregard for human life, striking Special Agent Bauer in the torso with a single gunshot.”

Authorities said Bauer died despite the medical efforts of agents at the scene, emergency crews and hospital staff.

Brown faces up to eight years in prison if convicted, according to prosecutors.

It was unclear Sunday if Brown has a lawyer who could speak on his behalf about the case. A call to federal prosecutors for additional information wasn’t immediately returned.