An armed robbery at a jewelry store in Florida ended with four people killed in a shootout Thursday after the gunmen hijacked a UPS truck and led police in a high-speed chase on a highway bustling with rush-hour traffic.

The two robbers, the UPS driver who was being held hostage, and a person in a nearby car were killed in the shooting in the Miami-area city of Miramar, Federal Bureau of Investigation agent George Piro told reporters. No law enforcement officers were killed.

A female employee of Regent Jewelers in nearby Coral Gables was injured, that city’s police force said. Her status was not immediately clear, Chief Ed Hudak told reporters.

The FBI on Friday identified the suspects as Miami-Dade County residents Lamar Alexander and Ronnie Jerome Hill, both 41.

The incident caused a shocking scene, snarling traffic and terrifying motorists caught in its midst along Miramar Parkway. Dozens of police officers from multiple agencies streamed onto the roadway, guns drawn, when the meandering UPS truck became boxed in by slow-moving traffic. As news helicopters hovered overhead, the officers fired a volley of gunshots at the truck, taking cover behind cars trapped in the gridlock.

Footage aired live on TV showed the truck getting riddled with bullets. Then, bodies fell from its passenger side and into the road.

“It’s unfortunate that the bystanders were killed, but the bad guys put all this in motion,” Steadman Stahl, president of the Miami-Dade Police Benevolent Association, told the Miami Herald. “Our thoughts and prayers are with the families of the two innocent bystanders.”

The episode began when Coral Gables police received a silent holdup alarm from the jewelry store in the city’s prized Miracle Mile promenade around 4:15 p.m., Hudak said. The Herald reported that the robbers were buzzed into the jewelry store because they were posing as postal workers. One of them fired into the floor; the bullet ricocheted, striking the female jewelry store worker.

In the 90 seconds before officers arrived, Hudak said, the two gunmen exchanged shots with the store owner. Some bullets reached City Hall across the street, and one hit a window, Hudak said. Employees were locked down, he said, and none were injured. But a photo taken by city clerk Billy Urquia, who heard the gunfire outside his office, showed how close the burst of bullets came. The image, shared with the Herald, showed a bullet hole in his office window, just over his computer monitor.

“The bullet ricocheted off the wall and landed on the floor,” Urquia told the newspaper. “The last one I heard was the one that came in.”

The robbers fled north in a truck and, about 20 minutes later, commandeered a UPS truck and abducted its driver at gunpoint while the driver was making a delivery in Coral Gables, Hudak said.

Several police cars chased the UPS truck on a highway in Broward County before the truck became stuck in traffic, leading to the fatal shootout. When the truck stopped in a middle lane, gun-toting officers swarmed it.

Those trapped by the traffic could only watch in horror. Three cars behind the UPS truck, a bewildered Avilo Rodriguez watched for bullets as he held his 9-year-old son Caleb down in the back of his SUV.

“You think about your life, but when your child is there, I mean, you’re just focusing on them,” he told NBC 6. “Keeping them down, keeping them down.”

First responders carried a stretcher from the truck to an ambulance. A picture snapped by a Herald photographer showed what appeared to be a body in the driver’s seat of a sedan, the vehicle’s windows obscured by tarps.

The FBI is leading the investigation. Police and the Bureau of Alcohol, Tobacco, Firearms and Explosives are assisting.

“The armed suspects engaged law enforcement in open fire,” the FBI’s Piro told reporters.

He said it would be “completely inappropriate” to discuss whether the UPS driver or the bystander may have been hit by officers’ gunfire.

“We have just begun to process the crime scene,” he said. “As you can imagine, this is going to be a very complicated crime scene.”

In the aftermath of the deadly shootout, witnesses shared startling images on social media — many showing graphic scenes and gunfire.

“This is what dangerous people do to get away,” said Hudak, the Coral Gables police chief. “And this is what people will do to avoid capture.”

Hudak said he did not know whether the gunmen succeeded in taking anything from the jewelry store.

David Graves, a spokesman for UPS, said the company would cooperate with the probe.

“We are deeply saddened to learn a UPS service provider was a victim of this senseless act of violence,” Graves said in a statement. “We extend our condolences to the family and friends of our employee and the other innocent victims involved in this incident.”

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