WESTBROOK — A Prides Corner sandwich shop was robbed Monday night amid an investigation into a string of six armed robberies in six days in the Portland area that police believe may be connected.

Subway manager Kerri Consiglio said a white man, whose face was covered, entered the Route 302 sandwich shop around 8:34 p.m. and demanded that the employee on duty open the cash drawer. During the encounter, the robber could be seen carrying a handgun that was tucked into his waistband, said Consiglio, who wasn’t in the store at the time of the robbery.

However, the suspect never drew the weapon or threatened the employee with the gun, instead he spoke in a friendly manner telling the worker to “keep the change” – after he took about $200 in cash from the drawer.

The robber appeared to be alone and he fled on foot, Consiglio said.

No one was injured. Westbrook police investigating the robbery weren’t available to comment Monday night on whether the latest robbery is connected to the six previous holdups.

The suspect appeared to be about 5 feet, 10 inches tall, the employee told Consiglio. The man was armed with a black handgun and was wearing a dark blue hooded sweatshirt and dark pants, according to a statement Westbrook police issued late Monday.

Police have said the suspect in the other robberies is about 5 feet 5 inches tall. He displayed a gun with a silver top slide and a black lower frame, police have said.

A Chinese restaurant on Washington Avenue in Portland was the sixth business in the area robbed at gunpoint in the past week.

China Taste, 1223 Washington Ave., was held up around 8:40 p.m. Sunday by a suspect who displayed a firearm. The suspect escaped without cash as he was interrupted by staff who came out of the kitchen, Portland Police Department Lt. Robert Martin said.

At a press conference Monday afternoon, Martin said the physical descriptions and mannerisms of the robbery suspects are similar.

“I can’t say for sure the same perpetrator has committed all six robberies,” Martin said. “The gun, height and general description of robber are generally the same.”

The six robberies since March 20 all involved a man wearing a face mask who used a handgun and calmly demanded cash, Martin said. No one has been hurt in the holdups. The FBI has joined police in Portland, Westbrook, Falmouth and Cumberland in the investigation, Martin said.

The first robbery was March 20 at the Riverton Gas Station on Forest Avenue in Portland.

On March 21, Falmouth police searched for a man who flashed a gun at the Lil’ Mart store on Route 1 around 8 p.m., then fled with some cash.

The Good Things Variety on Saco Street in Westbrook was robbed around 1 p.m. March 22. Police unsuccessfully tracked the robber with a dog.

Later that day, Cumberland police said someone robbed the Irving gas station a 174 Main St. at 8:44 p.m.

On March 24, a man brandishing a handgun entered the Daily Grind drive-through on Main Street in Westbrook shortly before 8 a.m. and threatened the clerk. The suspect fled on foot, according to Westbrook police.

“A person armed with a firearm and closeness and proximity to the crimes elevates this to a desperate person who will likely continue to do what he is doing,” Martin said.

Police are also hoping those living near the robberies have videos showing a potential getaway vehicle, Martin said.

Staff writer David Harry contributed to this report.

The man who robbed the Riverton Gas Station in Portland last week, shown in a security camera image, was described as white, about 30 years old, 5 feet 5 inches tall with a thin build. He was wearing a heavy dark jacket, dark cap, dark gloves and a half-face ski mask.