38-year-old Richard Wolley is being held under a $25,000 bond for aggravated robbery after being accused of trying to rob a pharmacy inside a Walgreens.
Investigators say the homeless man demanded narcotics and then displayed a handgun.
Officers were able to arrest Wolley as he was exiting the store.
A suspect is in custody after he attempted to rob the pharmacy inside the Walgreens at 2400 North Broadway shortly after 3:40 on Sunday afternoon.
According to a Knoxville Police Department press release, the man demanded prescription pills and then showed a handgun. A store employee, who witnessed the attempted robbery, hid within the store and called police. The employee gave officers a detailed description of the suspect and informed them when the alleged robber began leaving the store.
Officers arrested the suspect in the front of the store as he was headed towards the exit. Police said they found drugs witnesses reported the suspect stolen from the pharmacy, along with the pistol.
No one inside the store or the suspect was injured during the attempted robbery, according to the press release. Authorities said the suspect is probably in his fifties, but they do not know his identity at this time. The suspect has been charged with aggravated robbery.