Andre Perez was working on his car while his sisters practiced violin on the steps of their Las Cruces trailer home Saturday afternoon.
Perez was shirtless, which drew the ire of his front-door neighbor, 30-year-old David Vallejos, and the two began arguing.
Marcella Perez told police that her brother went inside his home and retrieved a shotgun. She said he placed the weapon by the front door and returned to car, only this time, he had removed his pants and was working in just boxer shorts, which police said further agitated Vallejos.
Another argument ensued, and it quickly escalated.
Marcella Perez said Vallejos rushed at her brother, and that's when Andres Perez retrieved a retractable baton from his car and allegedly swung at it at Vallejos.
She said Valejos was able to take the baton from Andre Perez's hands, take him down, and begin beating him with the baton, hitting him in the head.
Marcella Perez told police she feared Vallejos would kill her brother, and she ran inside and grabbed the shotgun.
When she came back out, she dropped the weapon and ran to her brother. She said he was lying on the ground and was not moving.
Andre Perez then started getting up, Marcella Perez said, and picked up the shotgun.
She said Vallejos, who was still holding the baton, turned around and said, "You want more?"
Vallejos approached Andres Perez rapidly and was about 15 feet away before Andres Perez fired at him, hitting him, she told police.
Marcella Perez told police Vallejos fell to his knees before her brother fired another shot.
Another man, Edgar Castro, told police he also witnessed the shooting. He said he was helping his aunt move when he heard Perez and Vallejos arguing.
Castro said he stepped inside and came out to see Perez lying on the ground and Vallejo collapsing the baton.
Castro said he ran toward Perez and saw him pick up the shotgun.
Catro told police he told Andres Perez, "Don't do it." But Perez began pulling shotgun shells from the buttstock and began loading the weapon.
Castro said Perez shot Vallejos once, and then a second time when Vallejos was on the ground.
Several neighbors disarmed Perez.
Gabriel Dillenburg, who works for El Paso Electric and was doing repairs, said he ran inside the trailer park after hearing two gunshots.
He said he saw a man, Andres Perez, in boxer shorts and dripping with blood from his head.
Dillenburg said he saw a shotgun inside a car and told Perez to sit sown on a curb.
Dillenurg said he closed the car door and made sure Perez didn't leave before police arrived.
When the responding officer arrived on the scene, he said he saw a group of people around Vallejos, the baton on the ground and two spent 12-gauge shotgun shells near the body.
Officer W. Gonzalez said someone was trying to perform CPR on Vallejos before Gonzalez removed the baton and asked the people to back up.
Perez was charged with murder. He was booked in the Doña Ana Count Detention Center under a cash-only bond of $500,000.