Surveillance video showed the suspect, who was wearing a woman's wig, pull out a handgun as he walked into the store.
Police said the suspect waited for another customer to leave before he approached the worker at the counter. He ordered the clerk to fill his bag with cash as he continued to hold up his handgun. He immediately grabbed the sack containing an undisclosed amount of money and fled the scene.
"We're obviously concerned because any robbery is serious but the fact that he's armed causes us some concern," said Anaheim police Sgt. Rick Martinez.
Authorities believe the suspect is in his 30s or 40s and weighs about 185 pounds. He has a goatee and mustache and was wearing a T-shirt, gloves and sunglasses.
Anyone with information is urged to call Anaheim police at (714) 765-1959.
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