(Getty Images/iStockphoto)

A New Mexico man held a knife to his father’s throat and later cut the elderly man’s face — all because he was angry that his parents’ home did not have air-conditioning, authorities said.

Police said the wounds were the culmination of an hours-long rampage that began Wednesday when Robert Generosa was angered by the lack of air-conditioning at his parents’ house in Albuquerque, where temperatures were 88 to 90 degrees, according to weather reports. The 49-year-old is facing assault charges.

Generosa threatened to stab his parents, screaming and waving a knife Wednesday night and into the early hours of Thursday, according to a criminal complaint. He later left the house and returned Thursday evening, and threatened his parents again, held a knife to their faces and threw the weapon toward the walls, the complaint says.

Robert Generosa (Albuquerque Police Department)

Later, he told his father he would kill him and held a knife to his throat, according to the complaint. At some point, Generosa left the room, giving his mother a chance to call 911. As she was on the phone, Generosa assaulted his father, cutting his face several times and striking the top of his head with the knife handle, the complaint says.

His mother told the dispatcher that she was unable to talk, but she stayed on the phone, allowing the 911 dispatcher to hear the struggle and the voice of a man screaming, the complaint says.

Generosa’s parents, whom authorities did not name, told police that they fear their son will kill them. They’ve since been taken to a hospital.

Generosa has been charged with assault against a household member with intent to commit a violent felony and aggravated battery against a household member with a deadly weapon. He was arrested Friday and was being held in the Bernalillo County Detention Center on a $5,000 cash bond.

During a hearing Saturday, a judge asked Generosa whether he knew why he was in court.

“Yeah, it’s disgusting,” he said, according to KOAT.

His father, whose face was covered with a large bandage, told a KOAT reporter that his son had a mental episode.

It’s unclear what mental issues, if any, Generosa was suffering from. The Albuquerque Police Department did not return a call seeking comment. A spokesman for the Bernalillo County district attorney said the agency has no further information to release. It was unclear whether Generosa had an attorney.

William Gray, a neighbor, told KOAT that the incident was a shock and that Generosa has always seemed “a nice individual.”

Records show that Generosa does not have a violent criminal history. He pleaded guilty to a misdemeanor drunken driving offense in 2012. He was charged with possession of marijuana and operating a vehicle while in possession of an alcoholic beverage, but those charges were later dismissed.

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