CYRIL, Okla. (AP) — A 4-year-old Oklahoma girl was reported missing and her caretaker was arrested on charges of neglect after a postal carrier found the girl’s 5-year-old sister wandering alone outside, authorities said.

Alysia Adams, 31, was arrested at the Grady County Sheriff’s Office and booked into jail in Caddo County on two counts of child neglect, the Oklahoma State Bureau of Investigation said in a statement late Thursday.

The arrest is related to the search for Athena Brownfield, who was reported missing Tuesday in Cyril, about 70 miles (110 kilometers) southwest of Oklahoma City, the bureau said.

A postal carrier found Athena’s sister outside Adams’ home Monday afternoon and alerted Cyril police. Authorities determined Athena was missing. The girls had been in the care of Adams and her husband, and Athena’s sister was taken into protective custody, the bureau said Wednesday.

The bureau released no additional information about Adams’ arrest, and it was not immediately known if she had an attorney who could comment on her behalf.

Authorities said they believe Athena was wearing a hoodie with a butterfly design when she disappeared.

The bureau said it was working with other law enforcement agencies and volunteers in the search, which included a helicopter and a specially trained ground team, as well as a review of surveillance video from around Cyril. It said agents were following up on tips coming from Oklahoma and other states.