(Reuters) - An elderly woman robbed a Colorado bank by passing a note saying she would infect a teller with AIDS if the clerk didn't hand over money, police said on Friday.

Jeff Satur, spokesman for the Longmont, Colorado police department, said detectives are searching for a pale woman between the ages of 55 and 75 with a "boney build."

Satur said a woman, who was wearing a train conductor's cap and a gray sweat shirt, walked into a Wells Fargo bank inside a Safeway grocery store on Thursday night and handed a note to a teller.

"She indicated she had AIDS and would give it to a teller if she didn't cooperate," Satur said.

The woman coughed frequently into a blue bandana during the robbery, and fled with an undisclosed amount of cash, Satur said.

Police and the FBI released still photographs of the robbery and are reviewing additional photographs and surveillance video from the bank's parking lot to try and identify the suspect.

She is described as about 5-feet 6 inches tall, and weighing between 130 and 150 pounds.

No weapon was displayed during the robbery and no one was injured, police said.

(Reporting by Keith Coffman; Editing by Dan Whitcomb and Jerry Norton)

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