The suspect in a Frankfort Square gas station robbery was hiding in the women’s bathroom at a McDonald’s restaurant, police said.

On Sunday, Sufyan Farhan, 27, of Frankfort, was arrested following the investigation of an armed robbery at Circle K gas station, 7654 W. Lincoln Highway, in an unincorporated community known as Frankfort Square.

Online court records did not show any formal charges against Farhan as of Monday evening.

During the investigation, Will County sheriff’s deputies learned a masked man who entered the gas station and brandished a knife, according to the Will County Sheriff’s Office.

The masked man claimed he had a gun and then he demanded money from the cash register, police said. The gas station employee complied with the masked man’s request.

“Shortly after deputies arrived, an individual came forward and advised deputies that he believed the suspect was a relative who had recently left their residence wearing a ski mask,” police said.

A reverse 911 alert was issued to nearby residents to shelter in place so deputies could search for the robber, police said.

Farhan was identified by deputies as the suspect and he was found “hiding in the women’s restroom of a nearby McDonald’s,” police said.

Deputies found a “large amount” of cash from Farhan, who was “positively identified” as the robber, police said. The investigation also led to the recovery of Farhan’s jacket and knife in a field just west of the McDonald’s.