Shannon J. Miles is charged with shooting Harris County Sheriff's Deputy Darren Goforth in the back of the head, firing a total of 15 times. (AP)

A man arrested Saturday in the shooting death of a sheriff’s deputy at a Houston gas station Friday has been charged with capital murder, Harris County Sheriff Ron Hickman told reporters at a news conference Saturday evening.

[Texas sheriff’s office identifies defendant in deputy’s ‘execution-style killing’]

Shannon J. Miles, 30, was picked up for questioning early Saturday, Hickman said, according to a Reuters report. The sheriff said the suspect apparently targeted sheriff’s Deputy Darren Goforth only because of his uniform.

Goforth had stopped to fill up his patrol car at a suburban Houston gas station Friday night when a man approached from behind and “literally shot him to death,” Hickman said.

Hickman said Miles has a previous police record, including charges of resisting arrest and trespassing. He was being held Saturday in Harris County.

Goforth, 47, died after being shot several times in what Hickman described as “an unprovoked, execution-style killing of a police officer.”  Goforth, a 10-year veteran of the force, is survived by a wife and two children, ages 5 and 12.

“We have not been able to extract any details regarding a motive at this point. As far as we know, deputy Goforth had no previous contact with the suspect, and it appears to be clearly unprovoked,” Hickman said.

The manhunt for the gunman stretched into Saturday afternoon as authorities pleaded for the public to provide any tips about the shooting. Investigators said they believed Goforth was targeted for his uniform and described the working motive as “absolute madness.”

But in speaking about the incident, authorities also referenced the broader national conversation regarding the relationship between law enforcement and the communities they police. Hickman said there was a “dangerous national rhetoric” regarding police.

“At any point where the rhetoric ramps up to the point where calculated, cold-blooded assassination of police officers happen — this rhetoric has gotten out of control,” Hickman said. “We’ve heard ‘black lives matter,’ ‘all lives matter.’ Well, cops’ lives matter too. So why don’t we just drop the qualifier, and just say ‘lives matter,’ and take that to the bank.”

Goforth is the 23rd officer to be shot and killed in the line of duty this year, according to the Officer Down Memorial Page, a nonprofit group that tracks line-of-duty fatalities. Fewer officers were shot and killed during the first half of 2015 than during the same time period in 2014, according to the group.

The deputy had finished working a routine incident and stopped at a Chevron to pump gas into his car. “A male suspect came up behind the deputy and shot the deputy multiple times. The deputy then fell to the ground,” Harris County Sheriff’s Deputy Thomas Gilliland told reporters Friday night. “The suspect then continued over to him and shot the deputy again multiple times as he laid on the ground.”

A witness called 911 to report the shooting, Gilliland said. Hickman said the earlier incident Goforth worked on and the shooting appear to be unrelated.

Police released grainy surveillance photos and guessed the suspect to be between 20 and 25 years old. He fled the scene of the shooting in a red or maroon Ford Ranger truck. Authorities spoke with an individual Saturday morning as part of the investigation, a Texas Department of Public Safety spokesman told The Post. No suspect has been named and no one has been taken into custody, Hickman said.

Surveillance footage shows several other people coming and going through the gas station at the time of the shooting, Hickman said.

“Please come forward if you have any information. It is time for the silent majority in this country to support law enforcement,” District Attorney Devon Anderson said at a Saturday news conference. “There are a few bad apples in every profession. That does not mean there should be open warfare declared on law enforcement. The vast majority of law enforcement are there to do the right thing.”

A representative with Houston-based 100 Club, a nonprofit organization that supports the families of officers and firefighters killed in the line of duty, said the group will give $20,000 to Goforth’s family to help “with immediate needs.”

“It’s a a very, very tough moment right now for the Harris County Sheriff’s Office,” Gilliland said. “I would ask that you keep us in your prayers and your thoughts.”

[This post has been updated.]

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