SAN CLEMENTE – What started out as a call about a loud radio early this morning ended with the arrest of a nude 26-year-old man who officials suspect killed a family dog with his bare hands, then poured hot coffee on his head while running naked in a tennis club, authorities said.

The dog’s owner said that if her 5-year-old mini schnauzer hadn’t run out in between her and the man, she would have been the one beaten to death.

“Rather than grab me, he focused on Kokanee and took his aggression out on her,” said Julie Donnelly, a nurse. “When Kokanee ran out in front, it gave me valuable seconds, valuable time to yell for people to help.”

Bayron Reyes Lopez has been arrested in the attack.

Investigators suspect that Lopez was under the influence of drugs when the pandemonium began shortly after 4:30 a.m., when deputies tried to contact him at his apartment.

Deputies were called to an apartment building in the 1100 block of Calle del Cerro because of a loud radio, said Jim Amormino, spokesman for the Orange County Sheriff’s Department. When deputies arrived, however, no one was there.

“We get there, go in the room, the guy is gone,” he said.

Authorities believe Lopez jumped from a third-story window when deputies arrived.

Deputies looked around for him and couldn’t find him, Amormino said.

He appeared to have turned up at 6:09 a.m., Amormino said, when dispatchers received a call from Donnelly screaming about the violent attack on her dog.

Donnelly, who walks every morning with a friend, was going to meet her up the hill on Calle del Cerro. But then a screaming man, who was clothed, ran down the hill, grabbed her dog and started to choke it. The man repeatedly hit the dog and slammed it onto the sidewalk, Amormino said.

Neighbors gathered around Donnelly as the man beat the dog. No one approached him, but he taunted people to come fight him, she said.

“I wish I could do something for Kokanee, but there was nothing I could do,” said Donnelly, who was going to bring her 13-month-old son, John, on the walk that morning, but decided not to.

The man held the dog for a few feet as he ran away and then dropped it on the side of the road. Kokanee, who the Donnellys have had since she was 8 weeks old, crawled for a few feet as Donnelly ran toward her and then the dog collapsed onto her side.

Minutes later, authorities received another call. This time, a caller reported that a man was running naked in the Rancho San Clemente Tennis Club, 111 Vista Montana. Officials say that the man was seen pouring hot coffee on his head.

Police arrested Lopez, a maintenance man at the club for three years, at the club. He was naked when he was arrested. They took him to Mission Hospital in Mission Viejo and then transported him to the Men’s Central Jail in Santa Ana. He is being charged with cruelty to animals and may be charged with being under the influence of drugs and narcotics if that is confirmed, Amormino said.

Kokanee died in Donnelly’s arms while being transported to a veterinary hospital in Mission Viejo. Donnelly said she tried to give her CPR, but it didn’t work.

A bucket of sunflowers with a photo of Kokanee wearing a red jingle-bell collar and licking her nose marks the median near the spot where she was beaten. A sign says “We love you Kokanee. Rest in Peace.”

“She was like a family member,” Donnelly said. “She sacrificed her life for me this morning.”