An Airway Heights prison guard was arrested Tuesday in connection with an armed robbery at a Dollar Tree store in Cheney.

Jeffrey J. Pool, 22, is suspected of ambushing the assistant store manager in the employee restroom at closing time Saturday, then holding the manager and another employee against their will in a warehouse in the store.

There still were customers in the store at the time, and Pool allegedly released the store manager so he could ring up their purchases, Cheney police said in court documents. While that was happening, Pool allegedly held a gun to the other employee within sight of the cash registers.

Once the customers were gone, Pool emptied the cash registers and fled the store, the document said.

The assistant store manager told police the robbery had “very stark similarities” to a robbery at the same Dollar Tree store on May 30, 2015, the document said. In both cases, employees believed the robber had “intimate knowledge of the inner workings of the store,” and was likely a current or former employee, it said.

Pool worked at the Dollar Tree, at 2424 First St., about two years ago, Cheney police said in the court document.

The suspect, who was wearing dark pants and a utility belt, used zip ties as handcuffs on the manager and another employee. All three items match gear worn and used by guards at the Airway Heights Corrections Center, a state prison, the court document said.

Pool was arrested as he reported to work at the Airway Heights prison on Tuesday, Cheney police said. He’s being held in Spokane County Jail on charges of robbery, assault and unlawful imprisonment. His bond was set at $500,000.