HOUSTON — The manhunt continues this weekend for the killer of 7-year-old Jazmine Barnes.

The little girl was killed Sunday morning when a shooter opened fire into her mother's car near Wallisville Road and Beltway 8.

Hundreds of ralliers packed a Walmart parking lot Saturday afternoon near the location of the shooting demanding justice.

"It is going to be justice for her," said the girl's mother LaShonda Washington as she addressed the crowd. "It is going to be justice because there are too many people out here looking for this man."

A crowd of demonstrators this size is rare for criminal investigations.

"I've been a victim advocate for over 25 years," said crime victims' advocate Andy Kahan. This is one of the largest outpourings of support I have ever seen for a homicide. The killing of a 7-year-old girl has struck a chord not just with Houstonians, not just people from the state of Texas, but this has galvanized the entire country seeking justice for Jazmine."

Many in the crowd believe the killing could have been racially motivated.

United States Congresswoman Shelia Jackson Leigh (D) said the murder appears to have been a hate crime.

"Our baby is dead," said Jazmine's uncle Otis Washington. "You all do whatever you all can to bring this murderer to justice. This community does stick together as Texans and we need to do whatever we can to find this killer."

Harris County Sheriff's deputies released an artist's sketch of the killer earlier in the week that was based on the account of Jazmine's sister, who was riding in the car when it happened.

The girl said she made brief eye contact with a white man, with beard stubble wearing a hoodie. He was reportedly driving a red pick-up truck.

The artist's image has circulated throughout the country and was printed on fliers handed to ralliers Saturday.

WATCH: Justice for Jazmine: Many leads from sketch

Speakers took to the microphone demanding justice, pleading with the killer and anyone with information to come forward.

"Please help me," Jazmine's grandmother pleaded as she broke into tears. "I could die tomorrow and never know. Please. Help me get him."

Sheriff Ed Gonzalez spoke at the rally pledging his deputies' commitment to catching the killer, but did not provide specific updates on the investigation.

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