Everything seemed business as usual at Granite Gulf on Cedar Street Thursday, with cars at the pumps and customers sitting inside, waiting on cars being serviced.

But the employees of the service station are still shaken by the armed robbery Wednesday, in which a man with a handgun fired two rounds inside the business before fleeing with cash.

Karin Kaye, who manages the family-owned business with her sister, said employees are still upset. The business will close early Thursday, she said, once it gets dark.

The family is thankful that no one was hurt, but upset about the violence.

"Awful," Kaye said, when asked to describe the experience. She wasn't at the business Wednesday night, but her brother was among the employees accosted by the robber. The first employee who encountered the robber, a gas attendant, told Kaye that the man pointed the gun at his chest and demanded cash. When the attendant froze, the robber rotated the weapon a foot to the right, and shot a bullet into the men's room.

"He didn't know what to do," Kaye said, of the attendant. "He's the father of three kids. He froze."

When the gas attendant walked into the service garage, to find his boss, the robber followed him and shot a second round, which hit but did not explode an oxygen tank, Kaye said. "He approached the mechanic and said, 'You're being robbed'." The man made the employees stand together. Once he got what cash the shop had on hand, he fled. The robbery took no more than three minutes, Kaye said.

Much of it was caught on surveillance video.

Customers were outside at the pumps, she said, some left, unaware of what was going on inside. The business was robbed once before, 12 years ago, she said. And in that incident, she said, the robber locked an employee in a room before leaving, and was caught when he came back to let him out.

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Milford Police are continuing to investigate the armed robbery. Detectives returned to the scene Thursday. But no arrests have been made, Police Chief Thomas O'Loughlin said.

The robbery is thought to be related to a similar crime in Medway, also at a gas station, but in that robbery an employee disarmed the robber.

Uxbridge also had a robbery Wednesday night, but the crime is not thought to be related to the other two, said Police Chief Peter Emerick. A man robbed the Sir Charles Hallmark store, but did not present a weapon.