The man in the orange vest appeared in Mike Willcox’s back yard without warning and start attacking dogs.

By the time family members inside his Kingwood, Tex., home noticed the random figure striding past the backyard pool, it was too late. A large metal pipe wrench was already raised above the man’s head and he was swinging it wildly, attacking dogs at the Willcox family’s backyard.

Willcox’s terrified 4-year-old son watched the March 23 incident unfold a few feet away in the living room, Wilcox told CBS affiliate KHOU.

“Flash” — an 8-year-old Weimaraner bird dog — managed to dodge the first few swings, but eventually took a brutal blow to the side of his head. The hit left the dog with a bloody laceration under its left eye, a swollen, infected jaw and a concussion, KHOU reported. A second dog, who received blows to its body, is suffering breathing problems.

Willcox told the station that he’s been left with an estimated $2,000 in vet bills and a lot of frustration.

“Right in here where he got hit with the wrench, almost got his eye,” said Willcox, describing Flash’s injuries. “Never bitten anybody, very friendly. It was like the guy was swinging to kill.”

In an interview with Fox affiliate KRIV, Willcox added that the incident upset the family’s sense of safety.

“Here’s our dogs in their own back yard where they’re supposed to be safe and sleep or whatever but to be woken up by a stranger five or six feet away from them … I mean, it’s pretty upsetting,” Willcox said.

The assailant— whose name has not been released — was a worker with CenterPoint Energy, a natural gas and utility company serving the region.

He was there to disconnect the home’s meter, a CenterPoint spokesperson told The Washington Post.

The entire incident was captured on surveillance footage that Willcox posted on Facebook, where it has been shared more than 18,200 times.

By the time Willcox made his way outside to confront the worker, he saw the man take another swing at the other family dog, “Shutter.”

Willcox told ABC affiliate KTRK that he confronted the man and asked him why he didn’t initially knock on the door before strolling into the back yard. He said the man told him, “I don’t have to do that.”

“I told him to stop swinging his wrench at my dog, and he said, ‘If they come at me, I can swing if I want,” Willcox told the Houston Chronicle. “I’m going to swing it again if they come at me.”

He told KHOU the incident finally ended when Willcox told the man to leave.

“I said, ‘I need to know your name,’ and he’s like, ‘CenterPoint,’ ” Willcox told KHOU. “And I was like, ‘Okay, you need to get off our property before things get really ugly here.’”

This is not the first time a CenterPoint Energy worker has been accused of attacking a family pet. In 2007, a Houston family filed a police report claiming that a utility worker entered their back yard without warning — ignoring “no trespassing” and “beware of dog” signs — before striking the family dog with a two-by-four, according to KTRK.

“He saw the gentleman jump over the fence with a two-by-four in his hand,” Elaine Cerda, referring to her husband, told the station.