After tellers placed assorted denominations of bills in a white cloth bag, the man ran north on Ford Avenue and turned east onto Center Street, police said.
Bloodhounds from the Maryland State Police lost the trail near Lakin Avenue, police said.
Trooper 1st Class Charles Brehm, who is assigned to the Cumberland, Md., barracks, was in Frederick, Md., for K-9 training on Tuesday, he said.
"I just happened to hear it and started this way," he said.
In addition to the employees, there were three customers in the bank during the robbery, police said. Authorities would not reveal how much money was stolen, but FBI Special Agent Bob Sidow said bank robbers typically get far less than they believe they will.
State police and Washington County sheriff's deputies searched the surrounding area but could not find the robber, police said. Potter said authorities generally blanket the surrounding area after a bank robbery.
"If a guy's going from a bank, that's the last place we need a lot of people," he said.
Neighbors say they have grown accustomed to finding police at the bank.
"It's ridiculous," said Theresa Fraley, 21, who lives across the street from the bank.
Adam Cronise, 21, said he was lying on his bed when he heard a commotion.
"I heard the police dogs barking. That's the first I heard," he said. "My dogs started barking too."
Dana Cronise, 16, said she had a feeling the bank had been a robbery target.
"We got out here and I was like: `I bet it got robbed again,'" she said. "This bank gets robbed all the time."
The robber was described as a white man in his 20s, 5 feet 8 inches to 5 feet 10 inches tall, with a medium build. He was wearing a blue, zippered sweatshirt with a hood, blue jeans and white sneakers.
When he entered the bank, he was wearing a bluish-gray mask with holes at the eyes.
The bank gained national prominence after a daylight robbery last Sept. 13. The robbery was featured on an episode of "American's Most Wanted."
Potter said neither of the previous robberies appear to be related.
"If we had the same person, it would be one thing," he said. "But we have different people. Is it location? I don't know. People do what they do, I guess."
Sidow said banks in rural locations sometimes appear more inviting to would-be robbers.
"Some that are more isolated become more frequent targets," he said. "That appears to be why they're selecting this branch."