Police are on the lookout for a gold Ford F-250 that was stolen from a Jacksonville firefighter Friday morning after he jumped out of the pickup to help someone involved in a crash.

Mitchell Johnson, who had just left his shift at a fire station a couple of blocks away, noticed the accident near the intersection of Myrtle Avenue and Martin Luther King Jr. Boulevard.

"I saw it, stopped my truck, got out and went and checked on the driver of the vehicle," Johnson said. "One of them was possibly critical, so they received my complete attention."

While he was tending to the victims, he said that two teenage boys jumped into his truck and sped off.

WATCH: Dashcam video shows theft, Johnson giving chase

"I immediately just took off after and they backed down a side street," Johnson said. "I jumped in front of the truck and I was trying to get them to stop. They tried to run me over. I managed to get in front of the truck. I tried to grab my tailgate to get in the back of the truck and the truck. It's a diesel Ford F-250. When you put your foot down on it, it takes off."

The two teenagers got away with not only the truck, but all of Johnson's belongings, including his work uniforms, his wallet with his ID inside and his babies' car seats.

Johnson said he was doing the right thing and he doesn't understand why someone would target him. He said what happened really hurt his feelings.

"It's unbelievable that the people who dedicate their lives and put the job before their families to help others, to serve others ... when, one day, God forbid, you may need our help and we come to help you," Johnson said. "It's just unbelievable."

The F-250 is tan with a red firefighter's place in the front. The back left window has a firefighter sticker and the back right window has a U.S. Marine Corps sticker.

There were witnesses and dashcam video of the theft, but as of Friday afternoon, the truck had not been located.

Mitchell said he was able to get a good look at the two thieves because they walked over to ask what was going on before they hopped into the truck and took off.

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