The cause was published last month by the Naval Safety Command in a report outlining deadly incidents in the Marine Corps and Navy over the last 10 years. The report says a service member at Camp Pendleton was "fatally injured due to negligent discharge during [a] live-fire small-arms training exercise" on that date.
The Navy command confirmed to Military.com that despite an initial discrepancy in the report's timeline, the Pendleton death occurred the same day that Lance Cpl. Joseph Whaley was killed at the base's School of Infantry-West.
Originally, the Naval Safety Command listed the "Ground Class-A Mishap" death as occurring on Aug. 21, four days after Whaley's death. In a statement to Military.com on Tuesday, the organization said that date was incorrect, and the negligent discharge death occurred on Aug. 17.
"There is only one event, not two," said Jeffrey Jones, a spokesperson for the safety command. "We have updated the mishap summary to reflect the correct date."
The date of Whaley's death during the training event was first made public in a Marine Corps Training and Education Command statement last month. The Marine Corps did not provide any additional information on how he died.
The details and nature of the negligent discharge, which likely refers to a firearm death, was not provided by the Navy or the Marine Corps. It was unknown whether the death could have been avoided or if any other service members were involved in the incident.
Military.com originally asked a Training and Education Command spokesperson to confirm the connection between the Marine Corps report of the death and Navy safety report nearly two weeks ago, but they did not.
On Tuesday, a spokesman for the Marine Corps command, Maj. Joshua Pena, was notified of the upcoming publication of this story and referred questions back to his original statement in August.
The Marine Corps has previously said that the investigation into Whaley's death remains ongoing.
Whaley, a Tennessee native, was attending the Basic Reconnaissance Course, or BRC, a three-phase school that teaches Marines individual amphibious reconnaissance skills, patrolling, surveillance and communication, according to the service's website.
Whaley was classified as an infantry student at the time of his death. His family was notified of his death the day after it occurred, the Marine Corps previously stated. Before he attended BRC, Whaley graduated rifleman training at the School of Infantry-East at Camp Lejeune, North Carolina, one of two entry-level infantry courses in the Marine Corps.
Attempts to contact Whaley's family were unsuccessful.
An obituary described him as an avid outdoorsman and talented high school football player in Tennessee.
"Joseph 'Joey' D. Whaley, a beloved son, cherished brother, devoted grandson, faithful friend, loyal teammate, outstanding Eagle Scout, dedicated Marine, and a Christian committed to serving and protecting others," according to the obituary.
Beyond Whaley's death, the Marine Corps has had a string of publicly known losses that started earlier this summer.
In July, three Camp Lejeune Marines were found dead inside their vehicle outside of a gas station, the cause of which local authorities attribute to carbon monoxide poisoning from the car. Local authorities could not explain in August -- after the investigation was closed -- exactly how the Marines were exposed to the deadly gas, other than saying it generally emitted from the vehicle.
In addition to Whaley's death, four other Marines died in accidents in August. On Aug. 24, an F/A-18D Hornet crashed near Marine Corps Air Station Miramar in California, claiming the life of the pilot, Maj. Andrew Mettler.
Less than a week later, a V-22 Osprey crashed off the northern coast of Australia during a routine multinational exercise. Both pilots and the aircraft's crew chief died, but 20 other service members on board escaped the crash, though some were in critical condition. Both aircraft incidents are under investigation.
A sergeant studying at the Marine Corps University in Quantico, Virginia, was found dead in his vehicle earlier this month. The cause of death was not disclosed.
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