[UPDATE: Police release photos of suspect in Auburn Dunkin’ Donuts robbery]

AUBURN — A pair of Dunkin’ Donuts clerks locked themselves in a back office late Wednesday after a man with a gun entered the business demanding money.

The young women were not hurt in the 9 p.m. stickup. The suspect made off only with a jar of tips from the counter, and remained at large later Wednesday.

Police surrounded the Riverside Drive business after a clerk hit a panic alarm and reported the robbery in progress. For the first tense minutes, nobody knew if the gunman was still inside the building.

With guns drawn, officers made their way to a back door and ushered the clerks to safety. The Dunkin’ Donuts employees, one 18 and the other 22, nervously rushed across the street while police continued the search for a suspect.

The 22-year-old said she was behind the counter when the man came in, put a bag on the counter and told her to fill it with money. He was holding a handgun, she said.

The clerk immediately activated an alarm.

“That was it. I pushed the red button,” she said. “I told him, ‘OK, but I need to go out back to get the person who has the keys.'”

The clerk then went into the back room, told her co-worker that the business was being robbed and locked the door behind her.

Police were on the way, but the clerks said that from the back room, they could not see the security cameras. They had no way of knowing whether or not the suspect had left the building.

“We didn’t know if he had run away or what,” one clerk said.

While the clerks, coatless, shivered across the street, roughly a half-dozen police officers continued to surround the building.

“They’re everywhere,” one clerk said. “I’ve never seen anything like it.”

Roughly 15 minutes after they arrived, police entered Dunkin’ Donuts and determined the suspect was no longer inside. He was described as a white man wearing a dark hoodie and possibly blue jeans.

The clerks said he had been holding a black handgun when he came in and demanded money.

Police remained at the scene an hour after the robbery was reported. The suspect remained at large.

Roughly a half-hour before the stickup at Dunkin’ Donuts, a worker at Fielder’s Choice on Minot Avenue reported a man wearing goggles and a mask had approached the drive-through window. The clerk refused to open the window, police said, and the masked man ran off.

It was unknown if that incident was connected to the robbery on Riverside Drive.