A volunteer firefighter in New Jersey — who was only 21 years old and preparing to become a cop — was killed in a car crash while responding to a call on Christmas morning, officials said.

Members of her fire company were on their way back from the call when they came upon the scene of the accident, according to Hamilton Township authorities.

Natalie Dempsey, of Mays Landing, had been driving her black 2001 Honda Accord to the Mizpah firehouse — where she had volunteered for the past three years — when she lost control of the vehicle and crashed into a guardrail. Officials said she was on her way to suit up after receiving a report of a fire around 6:20 a.m.

“This one has hit us hard,” said Chief Jay Davenport, of the Mizpah Volunteer Fire Company.

“She was one of the most beautiful-souled people you could imagine,” he told NJ.com. “The world was lollipops and rainbows for that girl. Her smile can light up the room.”

Davenport noted how Dempsey was the vice president of the South Jersey volunteer fire squad, and she still managed to find time to train for the police academy, which she attended over the summer.

“[Her death] smashed my heart out,” he said.

The Mays Landing Fire Department, for which Dempsey also volunteered, was also hit hard by her passing.

“To our brothers and sisters at Mizpah Volunteer Fire Company 18-2 we stand with you and we mourn with you during this dark hour,” the department wrote on Facebook. “Natalie Dempsey, thank you for your service; we’ll take it from here.”

With Post wires