The latest robberies were Monday night at two Walgreens near the Harris County/Montgomery County line, but investigators believe he's been at it since September.
While no one has been hurt, the Harris County Sheriff's Office is concerned he is moving towards violence. Lately, he's been wearing a bulletproof vest and has told victims he has "nothing to lose," says investigators.
The man has been caught on surveillance video. He's armed and wears a hat or t-shirt with the word "police" on them to gain trust.
According to officers, he demands controlled medications like hydrocodone and Oxycontin and threatens violence if the employees do not comply.
Investigators believe he's hit pharmacies in Friendswood, Missouri City, Houston, Harris County and Montgomery County.
A witness told authorities he's the same guy who pretended to be a police officer during Hurricane Harvey and told people to leave their homes when they didn't need to. Looting may have been a motive then.
The robber has a large star tattoo on the right side of his neck. Monday night, he had it covered with a bandage. He is considered dangerous.
Authorities are warning the public and other agencies to "exercise extreme caution," if he's spotted.
The Harris County Sheriff's Office robbery division is working to identify him.
Anyone with information is urged to contact investigators at 713-274-9200 or Crime Stoppers at 713-222-TIPS. A $5,000 reward for good information is being offered.
You can also submit an anonymous tip at www.crime-stoppers.org.
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