The United States Navy says two of its fighter jets dropped four unarmed bombs off the coast of Australia during an abortive training exercise.
The planes dropped the bombs in the Great Barrier Reef, a World Heritage Site, during a drill on July 16, it has been disclosed.
None of the bombs exploded.
The U.S. Navy said in a statement on July 21 that the AV-8B Harrier jets intended to drop at a bombing range on nearby Townshend Island but that the mission was aborted.
The jets were low on fuel and could not land loaded, the navy added.
Each bomb weighed around 226 kilograms, according to NBC.
The Great Barrier Reef is the world's largest coral structure, rich in marine life that stretches for more than 2,600 kilometers along Australia's eastern coast.
The incident occurred during three weeks of joint U.S.-Australian military exercises known as Talisman Saber, according to "The Guardian
," in which around 28,000 military personnel participate.
The paper said a U.S. 7th Fleet spokesman did not respond initially on July 21 when asked via e-mail about potential environmental risks from the incident.
Based on reporting by AP and BBC