LUDINGTON, Mich. — Western Michigan authorities say two young children whose father failed to drop them off with their mother have been found safe in Key West, Fla.

The sheriff's department in Mason County, Mich., says that 4-year-old Douglas McCallum and 2-year-old Shelby McCallum were with 52-year-old Mark McCallum, who was supposed to drop them off on Thursday.

The department opened a parental kidnapping investigation after he failed to do so.

The department says both parents live in the Ludington area and there was a shared custody arrangement.

It says the children were found safe about 4:30 p.m. Sunday and says their father's in custody.