According to ABC11 affiliate WLOS, Gary Wayt attended a wedding for Portwood's brother on Saturday. Police said Wayt was missing by Sunday night.
Bryson City Police Chief Charlie Robinson told WLOS that the couple had recently gotten engaged, and traveled from Indiana for the wedding and to celebrate their engagement.
Police said Portwood and Wayt were staying at a rental cabin at Twin Oaks Lodge when he went missing.
Robinson said Wayt was last seen in a 2009 Nissan Rogue with Indiana plates. He was described as 6'1 tall and 205 pounds, bald with brown eyes.
"Sunday, they had some kind of disagreement. He left. And when he left, he grabbed his wallet and his keys and that was the last time he was seen," said Robinson. "Just one thing l think is unusual is, he just grabbed his wallet and keys. He left his other personal items there. He left his cell phone there."
Portwood said she and Wayt had planned to leave on Monday, but she decided to stay in the area until he was found.
"Family has not heard from him ... Talked to his parents, his siblings, his fiancée...," said Robinson. "None of his friends have heard from him. We're just trying to locate him and make sure that he's safe."
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Anyone with information on Wayt's whereabouts is asked to call (828) 488-3050 or (828) 488-2196 and ask for Chief Robinson or Assistant Chief Dover.