(WSB Radio) The last person to speak to a missing Union County woman still thinks she's alive.

Douglas Davis told WSB-TV he was talking to Kristi Cornwell on her cell phone when she was abducted August 11.

"I can only say that I knew she was being abducted," Davis said. "I knew beyond a shadow of a doubt that I heard (she) was screaming. I knew that meant something wrong. "

Davis said he was in Atlanta at the time of the kidnapping. The Georgia Bureau of Investigation has confirmed he was the last person to talk to Cornwell.

"They were able to prove my whereabouts by my telephone, they knew where I was the moment this occurred," said Davis. "I volunteered for a polygraph. It took a couple of days, but we cleared that test as well."

Cornwell, 38, has a 15-year old son. She once worked as a probation officer. Davis said he and Cornwell had talked about getting married. He said they met on the internet in a Christian chat room and have known each other for about seven weeks.

Police believe Cornwell was abducted while walking down a rural road near her home in Blairsville. Search crews have been unable to catch a break after finding her cell phone last Friday.

The GBI called off the ground search on Wednesday. The FBI has brought in a kidnapping profiler to assist in the search and technical help to decipher cell phone connections made in the area at the time of Cornwell's disappearance. The FBI will also take a close look at security camera video from retail stores.

"I stayed above of the mountains where Kristi was taken for several days, and prayed, searching God for what I needed to do," Davis said.

Davis spoke at Hartsfield-Jackson Airport Friday. He was returning to Atlanta after making several appearances on network TV in New York. He still believes Cornwell is alive.

The GBI has set up two tiplines for anyone who has information about the case. You can call 706-835-2900 and 706-835-2902.