(CNN) The father of a 7-year-old girl killed in a drive-by shooting pleaded with the public to help authorities in the manhunt for a gunman who opened fire on a mother and children in a car near a Houston-area Walmart.

"I just want anybody, whoever, out there that knows anything about the murder of my daughter, to just please step up as if it was your own," an emotional Christopher Cevilla told reporters on Monday. "Just put yourself in my shoes, in my family's shoes."

Jazmine Barnes

Jazmine Barnes, her mother and three siblings were driving near the store in northeastern Harris County close to 7 a.m. on Sunday when a man pulled next to them in a red or maroon four-door pickup truck and fired several shots, the Harris County Sheriff's Office said. Jazmine was killed at the scene, Sheriff Ed Gonzalez said.

Update on Wallisville: deceased child is 7 year old, may she Rest In Peace. Suspected shooter described as white male, 40s, a beard, driving a red truck. If you know anything please contact us asap. We need our communities help. cc: @CrimeStopHOU #HouNews — Ed Gonzalez (@SheriffEd_HCSO) December 30, 2018

Jazmine's mother, LaPorsha Washington, 30, was shot in the arm and Jazmine's 6-year-old sister was struck by shattered glass, the sheriff said. Two teens were unharmed.

Authorities were working to determine whether the shooting was random or targeted, and they are searching for the shooter. He is described as a bearded white male, possibly in his 40s, who was wearing a red hoodie, according to the sheriff's office. The victims are black.

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