GRANDIN (AP) - Two men robbed this small town's only bank at gunpoint after tying up two employees, authorities said.

The Dakota Heritage Bank was robbed shortly after 10:30 a.m., Thursday, and authorities were looking for two men, Cass County Sheriff's Sgt. DuWayne Nitschke and Capt. Rick Majerus said.

Majerus said two employees were in the bank at the time of the robbery, but no customers. He said the employees were tied up, possibly to give the robbers more time to get away. The employees were not hurt, but "they were pretty shook up," he said.

"Normally around here, people come in, rob the bank and leave. They don't tie people up," Majerus said.

"It sounds like one (robber), while he was busy cleaning out the money, the other one was busy tying them up."

The amount of money taken was not disclosed. Authorities said the employees reported seeing one handgun.

Authorities believe the men drove off, Majerus said, but no getaway vehicle was spotted.

"You could go four different ways out there - a lot of roads out of there, and you don't know what to look for," he said.

Bob Mettler, a city worker, said he saw the two employees come out of the bank with rope still on their hands.

The robbery is "big shocker," Mettler said.

Nitschke said both suspects were wearing masks, and one of the masks was described as black with a skull-type design on it. He said initial reports indicated one of the suspects is black and one is white.