The bizarre motive was revealed in court, where a magistrate temporarily denied Miller's bond.
"It appears the defendant waved the police down and called the attention to the murder and freely admitted he shot them because they were allegedly performing witchcraft," Magistrate Eva Flores said.
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At about 8:10 a.m. on Saturday, Houston Police Department officers said they received a call from a passerby who allegedly saw a man aggressively waving a gun near an Exxon in the 1300 block of Neiman Lane.
Upon arrival, HPD Lt. Mark Contreras said Miller "blurted out that he killed a few people," including his cousin.
About a block away from where Miller was spotted, officers said they found two men and one woman who were shot in a wooded area where shipping containers were turned into a makeshift homeless encampment.
The woman and one of the men died from their gunshot wounds, according to police. The other man who was shot was taken to a nearby hospital in stable condition, Contreras said.
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"The defendant is alleged to have shot his cousin in the face five times, a visitor to the shipping container residence in the back of the head, and a third party, who was found alive, multiple times," Flores said.
Authorities identified one of the victims as Carlos Baltizar Canales.
When Police arrested Miller, investigators said he appeared to be mentally impaired the day of the shooting.
On Sunday, Miller was not present in court, and authorities ordered he undergo a mental evaluation.
Miller is due back in court on Tuesday.
ORIGINAL REPORT: 2 people killed, man arrested after 'aggressively' waving gun near gas station in NW Houston: HPD
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