The armed robbers who hit a Hopkins grocery last month and fled with tens of thousands of dollars from the safe had help from an employee who was working at the time, according to police.

The revelations of a suspected inside job came in a search warrant affidavit filed this week in Hennepin County District Court and confirmed Tuesday by Police Chief Brent Johnson to the Star Tribune as a "corroborated and correct" version of what went down late at night on Feb. 15.

So far, the suspected robbers, Darius C. Elam, 29, of St. Paul, and Ryan M. Elam, 28, of Brooklyn Center, have been arrested and charged with holding up the US Grocery and Tobacco in the 500 block of N. Blake Road.

At the time of charges being filed, Johnson said that what the store employees endured at the hands of the Elams "was horrific and deeply affected them."

The charges and an earlier related court filing say the Elams, who police believe are cousins, entered the store brandishing semiautomatic pistols. Two employees were bound and blindfolded with duct tape. The manager, threatened with her life and pistol-whipped in the head, gave the robbers access to the safe, which was left $45,000 lighter, the charges read.

The Elams took the employees' cellphones and other possessions, including the manager's gun, and stole an SUV that police later learned was owned by one of the four suspected conspirators.

A search warrant affidavit filed Monday by police that asked a judge for permission to search the SUV used as a getaway vehicle, however, now paints a clearer picture of how the crime was planned and executed:

Police and the FBI monitored Ryan Elam's jail phone calls and heard her tell her girlfriend to "keep her mouth shut," the court document read.

On Thursday, the girlfriend admitted to law enforcement that the Elams and two women — one of whom worked at the store and the other who owned the SUV — planned the robbery. She added that she was present when Ryan Elam discussed the plan, including to have an all-female crew working at the time of robbery "to avoid having any male employees working that would cause them greater difficulty," the filing noted.

The girlfriend said the deal was for the Elams and the two women to split the stolen cash evenly. She added that the conspirator who worked there was spared injury during the holdup. As of Tuesday, "no significant amount of cash has been located," the police chief told the Star Tribune.

After the robbery, the girlfriend continued, Ryan Elam called her on FaceTime and held the stolen cash up to her head. The Elams also bragged about pistol-whipping the manager.

The employee believed to be in on the plot was arrested Friday and admitted to law enforcement before her release that she knew about the robbery beforehand. The owner of the SUV also confessed to colluding in the scheme.

Charges have yet to be filed against anyone other than the Elams as the investigation continues, Johnson said. The Star Tribune generally does not identify suspects before they are charged.