Authorities say they have searched the home, office and vehicles of a man they think was the last person to see a Hilton Head Island couple who disappeared a week ago.

Beaufort County Sheriff's Lieutenant Neil Baxley says Dennis Ray Gerwing is a person of interest in the disappearance of John and Elizabeth Calvert and is not cooperating with authorities.

Baxley says Gerwing is in business with the couple.

The Calverts live part time on a yacht off Hilton Head Island and also own an Atlanta home. Family members reported them missing last week.

Baxley says Gerwing has an attorney but he would not say who it is. A phone message left at Gerwing's office Tuesday was not immediately returned. There was no answer at his home.