The search is underway for a personal trainer who vanished after leaving a Planet Fitness in South Carolina almost a week ago, according to police.

Elena Katherine Moore, 39, was last seen walking away from the gym in Lexington, about a 20-minute drive west of Columbia, on Thursday, authorities said.

Moore was headed toward the woods behind a Lowe’s home improvement store when she vanished.

The Lexington Police Department said it had deployed a drone in the area where Moore went missing, but it was unsuccessful.

A more thorough search of the woods was performed on Monday. There was no trace of Moore.

“This was not a recovery operation, but rather a precise effort to rule out one less place Ms. Moore could be,” Lexington Police Chief Terrence Green said in a news release about Monday’s search.

Local and state officials, including the South Carolina Law Enforcement Division, helped with the search.

Lexington Police also released a photo on Facebook from Planet Fitness’ surveillance cameras, appearing to show Moore talking with two workers who were standing behind the front desk.

Moore is a personal trainer at Wolf’s Fitness Center in Lexington, ABC News reported, citing Missy Silcox, a public information officer with the police department.

She regularly visited Planet Fitness, where she left from on the day she vanished, according to authorities.

“This is very out of character for her,” Silcox told ABC News.

As of Monday, Moore has yet to be found.

Moore is described as a white female with brown hair and brown eyes. She is five-foot-seven and weighs about 120 pounds.

She was wearing an olive green zip-up hoodie and black athletic pants when she disappeared, according to authorities.

The Lexington Police have asked anyone with information about Moore to call (803) 358-7271.

Those who wish to leave an anonymous tip can also contact Midlands Crimestoppers at (888) 274-6372.

“We’re just hoping tips come in,” Silcox told ABC News. “Even the smallest tip could be the biggest thing for us to crack open this case.”