By Ivan V. Natividad, Special to MCIN

The mortar shell explosion that killed seven Marines in March at the Hawthorne Army Depot was caused by a lack of weapons training and command supervision, a newly released report obtained by the Marine Corps Times, states.

On Tuesday, the Marine Corps Times reported the 19-page command investigation attributes the fatal explosion to ìhuman error,î also bringing into question the familiarity that the service members had with the weapons they were using.

Marine Corps Times reports:

The investigation concluded that four factors contributed to the tragedy: inadequate training and preparation for the complexity of the exercise; improper mortar gunnery commands and firing procedures; a ìperceived sense of urgency and resultant hasteî within the mortar section during the exercise; and a systemic lack of supervision of the mortar section during the exercise and in the months prior to it.

The deadly explosion occurred on March 18, when Marines from Camp Lejeune engaged in nighttime warfare training at Hawthorne’s Army Depot, located in Nevada’s high desert.

During the live-fire exercise, a 60mm mortar round exploded in its firing tube killing seven Marines and injuring at least eight others.

The following day, the Pentagon decided to ban the use of 60 mm mortar rounds until a military investigation could determine whether the weapons were safe. More than two months later the 2nd Marine Division issued a statement saying the explosion was caused by the Marines’ inability to follow procedures.

According to the Marine Corps Times, investigations into the incident determined that the 60 mm mortar was safe when used by properly trained Marines.

The Associated Press reports that Lt. Adam Flores, a spokesman for the Lejeune-based 2nd Marine Division, said Wednesday the explosion was triggered when a Marine dropped a second round into a mortar tube that was already loaded.

According to the AP, two officers and a noncommissioned officer were relieved of their command after investigations into the explosion concluded.

Recently, military training accidents have claimed the lives of service members across the country.

WTOP reports that from Jan. 7 to Jan. 15, at least 12 service members died from training accidents and nine of them, from separate incidents, died within a 24-hour period.

While the Department of Defense doesn’t release specialized statistics on military training deaths, looking at data from the DoD’s Defense Casualty Analysis System (DCAS) gives a closer look at how often military service members die accidentally.

DCAS has tallied the causes of all service member deaths since the Korean War.

From 2000 to 2010 the average death toll of service members who died in an accident calculates to more than 500 deaths per year.

A Marine veteran who formerly served tours in Kuwait and Iraq did not want their name used in this story but said military training deaths happen more then they should, adding service members who die during training exercises are often not given the same attention and recognition as soldiers who die during war.

“Combat training is inherently dangerous,” the Marine said. “But when someone dies in that situation it is sometimes just an accident, and no one is to blame. But in the [Marines] someone has to take the fall, regardless. Even the ones that passed.”