An emergency medical technician in New York City was killed Thursday when she was struck and dragged by her own ambulance that had just been stolen, police said.

Police said Yadira Arroyo, 44, had stopped her ambulance in the Bronx at about 7 p.m. after being alerted that a man was riding on the back bumper of her vehicle. Police had initially reported that a bystander flagged her down to report a robbery.

When she exited the vehicle to investigate, the man jumped inside as Arroyo tried to stop him, police said.

The man put the ambulance into reverse, striking Arroyo, who fell and got caught beneath the wheels, police said.

#FDNY mourns the loss of FDNY EMT Yadira Arroyo, Station 26, who was killed in the line of duty tonight while serving our city. pic.twitter.com/b3KrzGabYE — FDNY (@FDNY) March 17, 2017

Video posted on Twitter by a bystander shows the ambulance speeding across an intersection with one of its doors open, its lights flashing and the body of one of the EMTs being dragged beneath the vehicle.

The ambulance then crashed into several parked cars and got stuck on a snowbank. A passing Metropolitan Transportation Authority K-9 officer subdued the 25-year-old suspect with the help of a bystander.

A second EMT was in the passenger seat of the ambulance as it was being stolen. She was being treated at a Bronx hospital for minor injuries, police said.

"I want to thank those good Samaritans who helped apprehend the perpetrator," Mayor Bill de Blasio said at the hospital. "A lot of heroism was on display amidst a great tragedy."

"It's a sad night for everyone in the department," said Fire Commissioner Daniel Nigro.

Police didn't immediately identify the man who was arrested. Arroyo was described as a mother of five and a 14-year fire department veteran.

The video captured both the arrest of the driver, and a scene of anguish as the second EMT kneeled, sobbing, over the body of her fallen partner.

Justin Lopez, 20, told the Daily News that he shot the video of the episode as his brother was driving.

"I was coming from the street, up to the red light and I just saw the ambulance, the sirens and lights, and I told my brother 'Look something's happening,' and then somebody just hopped in, and then he hit two cars and ran over the person," he said. "I realized he was hijacking the car."

