A Marine KC-130 (Courtesy of USMC)

The Marine Corps has grounded its entire KC-130T fleet of cargo planes, the same type of aircraft that crashed earlier this month in western Mississippi, killing all 16 aboard and marking the deadliest aviation accident for the Marines in more than a decade.

“Out of an abundance of caution, the Marine Corps took the prudent action not to fly our KC-130T aircraft in the wake of the mishap on July 10 until further notice,” said 2nd Lt. Stephanie L. Leguizamon, a Marine spokeswoman, in an email.

Defense News was first to report on the grounding.

The move to ground the 12 aircraft fleet, operated entirely by the Marine Corps’ reserve component, comes as investigators are still trying to piece together what exactly happened that day. The C-130 family of aircraft is known throughout the world as a Cold War-era workhorse and one of the sturdiest aircraft in the U.S. inventory, so the fact that one appeared to break apart at cruise altitude with little warning or radio call has baffled those in the Marine Corps aviation community.

One pilot with knowledge of the crash, who asked for anonymity because he was not authorized to speak to the media, said that the aircraft had snapped into two parts just in front of the wings, though he did not know the cause.

The aircraft that crashed on July 10 was from Marine Aerial Refueler Transport Squadron (VMGR) 452 with the call sign Yankee 72. It was flying from an airfield in North Carolina to Yuma, Ariz., to transport six Marines and one sailor from the 2nd Marine Raider Battalion, a Special Operations unit, when it went down. Aboard was the team’s ammunition and supplies, prompting bomb disposal technicians to respond to the two distinct crash sites near the town of Itta Bena, Miss.

[Multiple impact sites point to midair disaster in Marine Corps plane crash]

People on the ground told local news stations and the Associated Press that they heard a series of booms before looking up and seeing the four-engine plane spiral out of the sky.

The KC-130T is primarily used for cargo and refueling, and is one of the oldest versions of the KC-130 line.