The Catoosa County Sheriff's Office is stepping up their search for a woman who has been missing since Monday evening. Channel 3 spoke with the woman's sister about her disappearance.

Deputies are looking for 28-year-old Kelly Mcinnes. She's 5’5” and has blonde hair and hazel eyes.

Her sister, Erin Crane, says it's very uncharacteristic of Kelly to just leave like that. Crane was the last person to see her sister and has been working tirelessly with the Catoosa County Sheriff's Office and FBI to find her.

Kelly Mcinnes and her sister, Erin Crane, went to Florida over the weekend to see their father who was in the ICU.

After an emotional weekend, the sisters arrived back home in Catoosa County on Monday evening. They began unpacking and Mcinnes told her sister she was going to run some errands. Crane didn't think anything of it.

"She went off in her car, a white Tuscon, and I never saw or heard from her since then,” Crane told us.

An hour-and-a-half later, Crane called her sister. It went straight to voicemail and her messages wouldn't send. After almost two hours of no contact, Crane filed a missing person report.

Crane said, "Since then, I've called Apple, I've called her cell phone provider, they can't find it. Her find my phone wasn't set up, she's not logged into an iCloud right now, and all her social media is deleted."

The search has led to a lot of dead ends until this afternoon. Crane spoke with an FBI agent in Dalton who might have a lead.

"He sent some information over to the detective today, that seems good, that seems plausible. But nothing has been confirmed yet of her whereabouts, just a maybe, a huge maybe,” Crane told Channel 3.

She told me the agent received a tip that her sister’s license plate could be in the Atlanta area. The FBI is investigating this further to confirm if it was actually her car and if she was in it.

Crane says these past few days have been unimaginable.

"She was here last. I saw her last. It's my responsibility to keep her safe,” Crane said emotionally.

Crane doesn't know if her sister is aware that people are looking for her, but if she happens to see this, she has one request. Call their dad.

If you have any leads or tips, you are asked to contact Detective Clay Thompson with the Catoosa County Sheriff's Office at (706) 935-2424.

There is a $10,000 reward for tips that lead to her safe recovery.