Robert Brown|Massachusetts man vanishes while on family vacation in Hilton Head; search underway

A search is Robert Brownunderway for a Massachusetts man who went missing Friday while vacationing with his family in South Carolina.

The family of Stanley Kotowski, 60, have told multiple outlets that the man abruptly left their vacation rental home on Hilton Head Island and has since vanished. It's believed his disappearance could be due to a mental health crisis, his wife has said.

Law enforcement in Beaufort County, where the island is located, have since spent days searching for Kotowski, but have been unable to locate him or make contact, according to the sheriff's office.

Kotowski left vacation rental with no shoes or phone

Kotowski was last seen on the morning of Aug. 16 leaving the family’s vacation rental, shoeless and without his phone and wallet, according to a Facebook post from the Beaufort County Sheriff's Office.

In interviews with other media outlets, his family members, who are from Methuen near Boston, have said that Kotowski had been struggling lately with anxiety.

"He had, like, really bad insomnia for about a month," his wife Jackie Kotowski told ABC Savannah, Georgia, affiliate WJCL. "His anxiety just kept getting worse and worse and worse. And he started to get a little paranoid. He thought someone was chasing him."

Kotowski's son Zak told WJCL that his father is otherwise healthy.

"He's a strong person, he's athletic," Zak Kotowski told the outlet. "He could, even in a delirious state, shoeless, he could get a few towns over."

Sheriff's office continues search for Kotowski

The Beaufort County Sheriff’s Office has spent days conducting a substantial search effort, deploying canines, drones, and helicopters to locate Kotowski.

That search continued as of Tuesday afternoon, according to the agency's most recent update on Facebook.

Firefighters have since joined the search effort, combing residential and wooded areas. Kotowski's information has also been entered into national databases and sent out to agencies statewide, the sheriff's office said.

The sheriff's office said Kotowski was last seen wearing a dark Coors light T-shirt, dark-colored blue or black shorts and no shoes. Kotowski is described as 6 feet tall, about 200 pounds, with short brown hair and brown eyes. His family told media that he has a thick Boston accent.

Because the last sign of Kotowski came on a resident's Ring camera, investigators are hoping people in the area will review their home security cameras for leads on his whereabouts.

Anyone who has information regarding Kotowski can contact the Beaufort County Sheriff’s Office's non-emergency line at 843-524-2777.

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected]