GRAND PRAIRIE, Texas (CBSDFW.COM) – A Grand Prairie police officer has died after a crash on the President George Bush Turnpike Friday morning.

Officer A.J. Castaneda, 38, was killed after a driver lost control and hit him while he was running traffic enforcement at 10:40 a.m.

Castaneda fell from the overpass to the street below. Highway patrol has yet to determine why the driver lost control.

An off-duty Arlington police officer witnessed the accident, called 911 and tried to help Castaneda.

The 17-year-old driver who graduated from high school this week, wasn’t injured and there were no signs of impairment at the scene, or that the driver struck Castaneda intentionally, police said.

Castaneda was a five-year veteran of the force. He worked previously with the U.S. Coast Guard for eight years and Tarrant County Sheriff’s Department for six years.

A.J. Castaneda (Grand Prairie PD)

Grand Prairie Chief of Police Steve Dye announced the officer’s passing on Twitter, saying: “It is with deep sadness that I announce we have lost one of our @GrandPrairiePD officers this morning. Our department is hurting… our community is hurting… our city is hurting. Please keep us in your thoughts and prayers as we move forward.”

During a press conference Friday afternoon, Dye said that Castaneda was a model police officer who followed up on calls on his own time. Castaneda also bought pizza once a week for kids at a community rec center on his own dime.

“He was man of character, compassion and a work ethic second to none,” said Dye.

Castaneda was named 2015 Grand Prairie Patrol Officer of the Year and a 2017 North Texas Police Chiefs Association Officer of the Month.

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CBS 11 News profiled Castaneda last September after he saved a baby from choking. It happened at the Mid-Autumn Festival at Asia Times Square. “All of the sudden I see a lady run out of the entrance and she’s holding a baby,” Castaneda told CBS 11 then. “The child was just lifeless. The arms and legs were just dangling there as she ran towards me. She was Nigerian. Huge language barrier.”

Castaneda said he knew what to do and began giving the 1-year-old boy back blows until he spit out a white object and started breathing again. “I got kind of teary eyed because it’s very emotional,” he said. “You have a child’s life in your hands and it was very, very emotional.”

He was lauded as a hero in the community that day.

“To me he is a hero,” Asia Times Square CEO Matthew Loh said. “The more I know about A.J., the more I admire him. For him, he just thinks that’s everyday life. That’s amazing. That speaks volumes of his character.”

“Whatever I can do for the children of the world,” Castaneda said in 2018. “I want to give. Children are great. They’re our future.”

All northbound lanes of the road were shut down near Dickey Road as police investigated the crash.

No charges have been filed against the driver that stuck Castaneda.

Castaneda served in the U.S. Coast Guard and the Tarrant County Sheriff’s Office, but he grew up in Grand Prairie and never forgot his roots.

“On every Thursday, he would go back to the community where he grew up and buy pizza for the kids at the rec center, folks, this was of his own accords,” said Chief Dye.

Chief Dye said he made the most of his time on earth.

“He gave back as good or better than any officer I’ve seen in my 35 years.”

Officer Castaneda leaves behind his parents and two children, one of them with special needs for whom he travelled internationally to find experimental treatments.

The Grand Prairie Police Benevolent Association has set up an official donation page for the family of Officer Castaneda. 

On Friday night, Chief Dye tweeted about the support the department has received from the community, including before the Rangers game at Globe Life Park.

He tweeted, “Words cannot adequately express our appreciation @GrandPrairiePD for the outpouring of love and support as we grieve the loss of Officer Castaneda. Your thoughts and prayers will provide us strength as we grieve and move forward in honoring this exemplary officer’s legacy.”

https://twitter.com/ChiefDye/status/1137173925635530752