The suspect, a black man wearing a black-hooded sweatshirt, entered United Community Bank on Homer Road at about 9:30 a.m.
Carrying a silver semi-automatic handgun, he showed a teller a plastic bag and said, "Hurry up," said Chief John W. Gaissert.
He took an unknown amount of money from the teller and ran out of the bank. No one was injured in the incident.
At about the same time, "there was a red vehicle in a parking lot adjacent to the bank that was seen leaving at a fairly high rate of speed," Gaissert said.
"But we have not corroborated that he was actually in that vehicle."
Police haven’t gotten any leads that indicate the suspect had an accomplice, he added.
Bank video indicates that the suspect is 5-foot-10 to 6-foot in height and weighs 220 to 240 pounds, Gaissert said.
He also was wearing "what appeared to be gauze ... concealing his face," Gaissert said.
"We anticipate the FBI assuming federal jurisdiction in this case because (the suspect) did produce a weapon," the chief said.