CHICAGO (CBS) — Three weeks ago, a National Guardsman was killed at the corner of Lockwood Avenue and Palmer Street in Belmont-Cragin.

On Monday night, there were signs and encouragement from the family to find the shooter.

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As CBS 2’s Jermont Terry reported, Chrys Carvajal’s family members never imagined they would be forced to walk their Belmont-Cragin neighborhood posting flyers.

“We’re not going to give up,” said Carvajal’s sister, Jennifer Ramirez. “We’re going to fight.”

It was early on the morning of Saturday, July 3, at the start of the July 4th holiday weekend, when the 19-year-old National Guardsman was gunned down.

Chrys Carvajal

Chrys Carvajal (Supplied to CBS 2)

“He was off serving and protecting our country, and for him to come home – and not even a month of him being home – you killed my brother, and now my family is broken,” Ramirez said. “Our hearts our broken forever.”

Carvajal was walking to his car, leaving a party, when someone in a car opened fire.

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“You shot him in the back,” Ramirez said. “You’re a coward.”

Carvajal’s mother was still emotional and crying as she hit the streets with family. With each step, they drummed up awareness about the unsolved murder.

But they are letting the community know there is now a $10,000 reward in the case – money raised by family and friends.

“With the money, they’ll want to speak up and they won’t be afraid, and they won’t be afraid to help the community,” Ramirez said, “because right now, it was my brother.”

But the family believes no one is safe until the shooter is caught – no matter the ZIP code.

“Don’t think that because you’re living on a high-rise tower in downtown Chicago, your life is not at risk,” Ramirez said. “Everyone is at risk in Chicago nowadays.”

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Carvajal’s family said they will continue to leave flyers in this neighborhood and surrounding areas until they get the big break in the case.