Authorities entered the bunker where a 5-year-old hostage was being held after negotiations deteriorated, FBI Special Agent in Charge Steve Richardson told reporters.
After Jimmy Lee Dykes was seen holding a gun, FBI agents entered and rescued the boy, he said.
"The child appears unharmed" and the hostage taker is dead, he said.
The Midland City, Alabama, kindergartner freed from the underground bunker where he had been held for a week remained hospitalized Tuesday, according to Midland City Elementary School Principal Phillip Parker.
There is no time frame for his release, Parker said.
Alabama Rep. Steve Clouse told CNN, "Finally, this nightmare has come to an end."
A neighbor of Dykes said Monday he heard it end. "I heard a big boom and then I heard, I believe I heard, rifle shots," Byron Martin told CNN. "Literally made me jump off the ground."