In a series of profanity-laced text messages, Jason Boek told his on-again, off-again girlfriend that he was watching her “every move” from outside a bar in central Florida, authorities said.

She told him it was over.

Then, authorities said, he threatened to hurt her and an Uber driver who he thought had picked her up.

"I see y’all,” Boek wrote, according to an image of the messages released by the Polk County Sheriff’s Office. He added: “I’m going to [expletive] both of y’all up. Your a piece of [expletive]. I’m going to [expletive] beat the [expletive] out of Uber driver.”

But, authorities said, Boek’s girlfriend was not in the Uber — instead, she had walked another woman, whom she did not know, out of the bar in Dundee early Tuesday morning and helped the woman get into the car.

Boek apparently thought it was his girlfriend who was riding in the vehicle, according to the authorities.

Officials with the Polk sheriff’s office said in a statement that Boek, 34, “aggressively approached” the Uber from behind, then briefly pulled up beside it before cutting off the driver and forcing him to stop. Boek emerged from a pickup truck carrying an object in his hand, which turned out to be a cellphone, and shouted at the driver: “You know I got a pistol. You want me to [expletive] shoot you?” according to video released by authorities.

Authorities said the Uber driver, 38-year-old Robert Westlake — who is an armed security guard and is licensed to carry a concealed weapon — pulled a handgun and opened fire, fatally shooting Boek in the chest.

“You have the right to protect yourself,” Polk County Sheriff Grady Judd told reporters about the incident during a news conference Wednesday. “This is a classic stand-your-ground case.”

Grady added that Westlake “did exactly the right thing to protect himself and, ostensibly, his passenger.”

According to Florida’s stand-your-ground law, a person is “justified” in using deadly force when “he or she reasonably believes that using or threatening to use such force is necessary to prevent imminent death or great bodily harm to himself or herself or another or to prevent the imminent commission of a forcible felony."

The law states that the person "has the right to stand his or her ground if the person using or threatening to use the deadly force is not engaged in a criminal activity and is in a place where he or she has a right to be.”

It was about 2:20 a.m. Tuesday when Boek approached the Uber on Dundee Road in Polk County, about 60 miles east of Tampa. Dash-cam video shows Boek swerve in front of the Uber, stop his truck and then walk toward the Uber, threatening the driver.

A gunshot can be heard, and the car’s passenger shouts, “Oh, my God!”

The sheriff said that after the shooting, Westlake, who recently finished the police academy, called 911, speaking in “police lingo” and telling the dispatcher what had happened. The sheriff said that Westlake then attempted to stop the bleeding and performed CPR until paramedics arrived.

“He ran me off road, jumped out of his vehicle. I couldn’t get away," Westlake told the dispatcher, according to CNN. He added: "He came towards me, shouted he’s got a pistol, reached for his waistband.”

Westlake said he fired one shot, and it wasn’t until Boek dropped the cellphone that he realized what it was.

Officials with the county sheriff’s office said Boek, who was on probation for felony battery, has a criminal history that includes arrests for aggravated battery, burglary, forgery and larceny, among other things. During the incident Tuesday morning, he was driving with a suspended driver’s license, authorities said in the statement.

When deputies later searched the truck, which belongs to Boek’s friend, they discovered a marijuana cigarette and a glass pipe that contained methamphetamine residue.

A spokesman for Uber said in a statement Thursday to The Washington Post: "We are saddened by this unfortunate incident and will continue to work with police on their investigation.”

In a separate case over the summer in Clearwater, Fla., 48-year-old Michael Drejka shot and killed a man over a handicap parking spot after the man, Markeis McGlockton, shoved Drejka to the ground. As The Post previously reported, Pinellas County Sheriff Bob Gualtieri called Drejka’s actions self-defense but, earlier this month, state prosecutors charged him with manslaughter — reigniting a national debate about such stand-your-ground laws.

After Tuesday’s shooting, Judd, with the Polk sheriff’s office, urged citizens to “leave people alone.”

“At the end of the day,” Judd told reporters, “the message is clear: Don’t mess with the Uber driver. Leave the Uber driver alone — because he just may be a certified police officer in waiting.”

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