A week before the leadership team of 3rd Battalion, 6th Marines was relieved for a "loss of trust and confidence" in their abilities, five Marines in the unit were injured after an 81mm mortar round landed roughly 30 to 40 meters away during a training exercise, Task & Purpose has learned.

The Marines were assaulting through a live fire range in California known as Range 400 on March 6 when an errant high-explosive round landed nearby, peppering them with a small amount of shrapnel. Fortunately, all five Marines walked away with only minor injuries despite a round landing within "danger close" distance of friendly troops.

2nd Lt. Andrew Foster, left, a platoon commander, and Lt. Col. Clinton Kappel, the battalion commander of 3rd Battalion, 6th Marine Regiment, discuss suppression tactics during a live-fire and maneuver exercise on Range 400 at Marine Corps Air Ground Combat Center, Twentynine Palms, California, March 7, 2020. Lance Cpl. Jacqueline Parsons/U.S. Marine Corps

"The Marines are now back on full duty," said Capt. Nicole Plymale, a spokeswoman for the Marine base in Twentynine Palms where the incident occurred. "The incident is currently under investigation."

Although Range 400 is a live-fire range featuring overhead machinegun and mortar fire as rifle companies attack a fortified objective, the mortar targets are pre-planned and rounds usually land hundreds of meters away from Marines running the exercise.

"One tube was way out to lunch," a source familiar with the matter said on condition of anonymity.

Six days later, the unit's commanding officer, Lt. Col. Clinton Kappel, and battalion sergeant major, Sgt. Maj. Elson Aviles, were relieved of their duties. A spokesman for the 2nd Marine Division declined to elaborate on the reason.

Lt. Col. Clinton Kappel and Sgt. Maj. Elson Aviles

U.S. Marine Corps

"The circumstances surrounding the relief are specific to the leader-led relationship and thus not open for discussion," said 1st Lt. Dan Linfante, division spokesman.

The incident involving 3/6, which has not been previously reported, came a few months after the unit lost two rifles on a field exercise in Camp Lejeune, North Carolina. The rifles have not been recovered and an investigation opened in December remains open, according to an NCIS spokesman.

Kappel, 42, had been in command of 3/6 for less than six months, having taken command in Sept. 2019.

Kappel enlisted in the Corps in 1996 and later commissioned as an infantry officer and deployed multiple times to Iraq and Afghanistan, according to an official biography. Sgt. Maj. Aviles, 41, enlisted in the Corps in 1997 and trained as a combat engineer. He had deployed to Iraq, Afghanistan, and Syria.