Atlanta police said in a statement later Friday morning the caller also wanted $15,000 and an airplane. It wasn't immediately clear whether the caller made the demands from CNN or some other entity.
A search of the global news network's headquarters and the Omni Hotel turned up no sign of any bomb. The complex includes the hotel and several shops and restaurants.
Streets were reopened by 6 a.m. Friday, about two hours after the initial 4 a.m. call.
The U.S. Department of Homeland Security is investigating.
It wasn't known whether employees were evacuated. CNN representatives didn't immediately return phone calls.