Kristi Simonson, 33, and Charod White, 21, were arrested Friday after police say they were involved with motel prostitution and robbery.

According to the Gates Police Department, an undercover sergeant replied to an ad for "escort services." Upon meeting, police said Simonson accepted $80 in exchange for sex in a motel in Gates.

Police say Simonson went to the bathroom, and White then entered the room and threatened the undercover officer with a knife.

The two face charges including robbery, petit larceny, criminal possession of a weapon and prostitution.