A nationwide search-and-rescue team descended into Atlanta Saturday to help search for a missing CDC worker.

No one has seen 35-year-old Timothy Cunningham for almost three weeks.

"I heard about him on the news. I heard this was happening. I wanted to come out and help," said Bryan Thrasher, a search volunteer.

Saturday, Police, volunteers and K9 team searched a wooded area near a CDC office and the Mercer University Atlanta campus.

"These dogs are trained to find people. So we train all the time to disassociate critters from real people," said Gary Bonneau, President of the Alpha Team K9 Search and Rescue Group.

"We have a good skills. We have great dogs. We're just passionate about helping the community."

That passion is what's keeping volunteers going, even during the darkest times.

"I guess it's just the notion that he might be out there and I could do some good to help find him," Thrasher said.

Atlanta Police do not suspect foul play in Cunningham's disappearance. There is a $10,000 reward for information.