WASHINGTON ― Defense Secretary Jim Mattis is looking into whether the military has an inability to say “no,” and whether that culture may be part of the reason behind a spate of non-combat troop deaths in recent months.

Since June, at least 56 service members have been killed or injured in training incidents or regular operational maneuvers across all services.

In just over the last week alone, 20 service members were injured and two were killed in separate training incidents at Camp Pendleton, California, Fort Bragg, North Carolina, and Fort Hood, Texas.

This recent spike in training or non-combat incidents follows several years where both non-deployed and deployed units have seen a sharp increase in accidents and crashes, spurring operational pauses in the Air Force, Navy and Marine Corps.

In looking for causes, the services have previously said that training hours across the board have been reduced for forces, particularly for home-stationed units, in order to push the highest levels of readiness to deployed troops. The military has also said that the automatic budget cuts known as sequestration have increased the dangers to their forces by leaving them with less time to gain proficiency or remain current in flying, maintenance or other critical operating skills.

But even with less training, the services are having to meet increased demands for operations in both U.S. Pacific Command and U.S. Central Command. 

“I would say, having some association with the U.S. military,” Mattis said, referring to his decades of service as a U.S. Marine, “we’re almost hard-wired to say ‘can-do.’ That is the way we are brought up, routinely, and in combat, that is exactly what you do even at the risk of your troops and equipment and all.”

Mattis said he was not ready to draw the conclusion that senior military leaders pushed each branch to meet operational demands despite a lack of readiness, but he intended to find out. 

“I am not concerned right now that we are rewarding the wrong behaviors but we are going to find out if that’s the case and we are going to look at that.”

Mattis said the investigations will go beyond the specifics of each crash and determine “what is the culture” behind pressure to meet operational requirements when less training, spare parts or maintenance is available.

“We’ve got to find out why we’ve suddenly had this spate of incidents,” Mattis said, noting that in general, troops train in dangerous situations everyday ― such as practicing aircraft carrier landings or training with live ammunition ― and the vast majority of the time the training does not result in an incident.

“We are going to look at what happened on the demolition range. And we are going to look at what happened with the seamanship ... and we are going to look at what happened with an aircraft,” Mattis said, referring to the collisions of the destroyers Fitzgerald and John S. McCain that killed 17 sailors, an incident at a demolition range at Fort Bragg that killed one soldier and wounded seven others, and a crash of the U.S. Marine Corps KC-130T in Mississippi that killed 15 Marines and one Navy corpsman earlier this summer

Mattis said he had drawn no conclusions yet.

“I am not willing to say right now that there’s a direct line between sequestration and what has happened,” Mattis said.

But, he added “we are going to take a very close look at that.”