Authorities say four people have been charged with robbing a Central Florida woman three times.

The Polk County Sheriff's Office says the victim had been a landlord of one of the suspects arrested Monday.

The sheriff's office said the robberies occurred over one month.

The first robbery happened June 2 while the 68-year-old woman was getting ready to show a Lakeland house to a potential tenant. Donna Stark then was robbed at gunpoint two times, on June 10 and on Sunday, while she was walking to church.

According to an arrest affidavit, Stark didn't have money or credit cards in her purse Sunday, so one suspect hit her in the face with a gun and demanded that she take him to her home to get cash.