Charges for Andre Jackson were dropped and he is being released after being charged with Josue's murder over a year ago.
Josue Flores was just 11 years old when he was stabbed to death while walking home from Marshall Middle School last May.
WATCH: Timeline of the Josue Flores case
In early June 2016, 27-year-old Jackson was arrested. But today, the Harris County District Attorney's Office said his release comes down to DNA.
The Harris County District Attorney's Office said the results of the DNA in a blood analysis are "at best inconclusive" and "in some ways exclude" Jackson as a suspect.
No other suspects have been named, however, and prosecutors said Jackson remains a suspect despite their lack of enough evidence to convict him.
Jackson's attorney said these developments don't surprise him, because he was convinced he could not have committed Flores' murder.
Meanwhile, as the prosecution begins its case once again, there is a new call for the public to come forward with information to catch Flores' killer.
Josue's family said they are "devastated" after learning the charges were dropped against Jackson, who they still believe killed the boy.
In a statement to Eyewitness News, his sister Guadalupe Flores asked for privacy as she and her family deal with this new information.
"We are too devastated and broken up that a killer is being let loose due to insufficient evidence," Guadalupe Flores said.
"I know it doesn't matter what I think, but in my heart I know that he is the killer. But I know there's not enough evidence for them to keep him in jail, but that's how the system goes. If they don't have any evidence they have to let you go."
HPD released this statement on Twitter this afternoon:
ORIGINAL STORY: Ex-Marine charged in 11-year-old Josue Flores' murder
Investigators: Josue Flores stabbed 20 times
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