Walker County, Ga., emergency crews were called to Ellison's Cave near LaFayette late Sunday to try to rescue a caver who fell and was injured.
As of 10:30 p.m. Sunday, rescuers had reached the scene but hadn't made contact with the fallen caver.
"We are still trying to get people to him," Walker County Coordinator David Ashburn said Sunday night. "But we're in the infant stages."
Rescue crews were called about 6 p.m., but Ashburn said they still were working to contact the victim, who fell 40 feet down one of the most difficult caves to navigate in the country.
Because of the skill level required to maneuver safely through the cave, Ashburn said, the rescue crews typically called in for these events aren't qualified to perform the rescue. Crews were called in from Huntsville, Ala.; Knoxville; Nashville; and Chattanooga to assist.
Ashburn said the rescue could take more than 24 hours.
It is unknown if the victim is alive. Ashburn said crews will descend with medical equipment. In the event of a death, however, the coroner will be called to begin a criminal investigation into the accident.
According to Ashburn, four cavers were exploring the two deep pits that make up Ellison's Cave. One fell shortly after 4 p.m. His companions called out, but they couldn't hear anything. One climbed out to call emergency services while the other two remained inside.
"Our hopes are that he's just hurt and that they can't hear him," Ashburn said.