A 28-year-old man in Nevada was arrested this week after he allegedly killed his own father, fatally shooting the older man in his home while emergency police dispatchers on an open-line 911 call were able to hear two family members’ grisly final conversation. Isaac M. Velasquez, who allegedly graffitied the inside of his parents’ home with pentagrams and “666,” was taken into custody early Tuesday morning and charged with one count of open murder with a deadly weapon in the cold-blooded slaying of Manuel Velasquez, records reviewed by Law&Crime show.

Velasquez also allegedly attacked his mother, who was present when the altercation between father and son began, and was subsequently charged with an additional count of domestic battery with a deadly weapon.

Isaac M. Velasquez (Las Vegas Metropolitan Police Department)

According to a news release from the Las Vegas Metropolitan Police Department, Isaac Velasquez’s mother is believed to have called 911 at around 11:18 p.m. on Monday, Nov. 27, after she saw her husband and son fighting in the kitchen. According to police, when Isaac Velasquez threatened her, she fled and ran to a neighbor’s house — but she left the phone behind, the call to 911 still connected.

The dispatcher continued monitoring what had by then become an open-line call, and “the call taker could hear arguing and what possibly sounded like a gunshot,” police said.

While still on the line, the dispatch center received two additional calls. One was from a male — later identified as Manuel Velasquez — stating he had been shot by his son. The other was from a female — later identified as Isaac Velasquez’s mother, calling from a neighbor’s home — stating that her son just shot her husband inside the couple’s home

Officers responded to the residence located in the 9700 block of Horseback Circle. Upon arriving, first responders were able to locate Manuel Velasquez inside the master bedroom of the residence. He appeared to be suffering from multiple gunshot wounds. Medical personnel responded to aide the victim, but he succumbed to his wounds and was pronounced dead at the scene.

“The investigation by the LVMPD Homicide Section indicates the victim was in an altercation with [Isaac] Velasquez, who was holding a gun,” police wrote in the release. “During the altercation [Isaac] Valasquez shot the victim.”