No one was injured in the incident, which occurred shortly after 4 a.m. ET at the Kodiak Launch Complex in Alaska, said Maureen Schumann, spokeswoman for the U.S.
"The weapon exploded during takeoff and fell back down the range complex," Schumann said.
The weapon was developed by Sandia National Laboratory and the U.S. Army, as part of the military's "Conventional Prompt Global Strike" technology development program, which is seeking to build a weapon that can destroy targets anywhere on earth within an hour of getting data and permission to launch.
Schumann said officials from the program, the U.S. Army, Navy, and Missile Defense Agency were conducting an extensive investigation to determine the cause of the accident.
(Reporting by Andrea Shalal; Editing by Mohammad Zargham)