MILL CREEK — The story has repeated itself at least nine times since May.

A man enters a Mill Creek business. Sometimes he flashes a gun. Sometimes it’s a knife. He demands cash, then makes a quick, clean getaway.

Police aren’t sure it’s the same man every time, said Ian Durkee, a detective with Mill Creek police. The suspects in the robberies, many caught on surveillance video, appear to have different heights and weights. The choice of weapon varies.

Two things are fairly consistent: the precise wording of the demand and the getaway. The bandit has said the same thing in six of the robberies.

Police won’t release the exact phrase because it’s part of their investigation, Durkee said.

“It’s fairly original,” he said.

The detective thinks multiple people could be involved in the getaways. Some have been on foot; others have used bicycles or motor vehicles.

“It’s hard to say for sure whether it’s a group of people or it’s one person,” Durkee said.

The detective believes the robbery string started May 2. For awhile, they were happening every few weeks but have slowed in recent months.

Seven of the nine robberies took place at the Thomas Lake Shopping Center in the 3400 block of 132nd Street SE. Almost every major business has been hit, including one that was robbed twice.

“It’s pretty brazen,” Durkee said.

The other two robberies happened at a business only a few miles away. Again, they appear linked to the string by the robbers’ particular demand.

Thomas Lake Shopping Center has three private security patrols a night, 365 days a year, said Chris Daniell, a property manager with Regency Centers, which owns the shopping center.

This is the first time Durkee has seen a specific location targeted so frequently. He believes the suspect or suspects may live nearby. Most likely, they’re motivated by their past successes, he said.

“They’re just feeling bolder and bolder every time,” he said. “They feel safe committing their crimes there.”

An emboldened robber or robbers is worrisome, Durkee said. Business owners and employees at the center are getting frustrated and fed up. That may make them less likely to simply hand over the cash, and that could make a dangerous situation potentially deadly, the detective said.

“Victims can try to take action on their own and get hurt as a result,” he said.

Since the string of robberies began, police have stepped up patrols near the center.

“We’re doing everything we can to keep a lot of patrol officers in the area as much as possible,” he said.

Mill Creek police recommend all businesses owners get surveillance camera systems. Employees also need to be especially careful near closing time, a favorite time for the robber or robbers. Until the string is busted, Durkee recommends having multiple employees working at night.

The robber is usually described as dressed in a black hoodie sweatshirt, some sort of mask and jeans.

Police are asking the public to be aware and look out for suspicious activity. People casing businesses will spend unusual amounts of time watching, walking by, driving past or hanging around outside.

“If anyone sees those things (at the center), call 911 right away and keep an eye on the person,” Durkee said. “We’re gonna need other eyes besides our own to help us out on this one.”

Police urge anyone with information about the robberies to call detectives at 425-921-5704.