Authorities in Texas have arrested a small-town police officer on suspicion of fatally shooting his younger brother last week.

Stagecoach officer Robert Lee, 59, was reportedly at his home when he opened fire on a man authorities later identified as 57-year-old Rocky Lee.

The younger Lee also served in law enforcement and was a deputy with the Harris County Sheriff’s Office at the time of his death, as previously reported by CrimeOnline.

Both men were off duty at the time of the shooting. Reports indicate Robert Lee called 911 after his brother was shot, initially telling authorities he believed the man was a home intruder.

Police believe the victim was attempting to check on his older brother’s welfare on Friday when he was shot, according to the New York Post.

Robert Lee was arrested the following morning and booked into jail. Initial police statements on the arrest did not include details about expected criminal charges or information about his attorney.

Montgomery County investigators are in charge of the case and soon rebuffed early reports that a burglary attempt preceded the shooting.

“The exact circumstances surrounding the shooting are under investigation,” said Lt. Scott Spencer. “We don’t believe there was a burglary at the residence.”

Harris County Sheriff Ed Gonzalez expressed the sentiment of his department in a statement after the shooting.

He said colleagues’ “hearts are broken” and they will “be hurting for a long time” in the wake of the deputy’s death.

[Featured image: Robert Lee and Rocky Lee/Montgomery County Sheriff’s Office and Harris County Sheriff’s Office]