The plane was a KC-130 aircraft typically used by the Marine Corps for aerial refueling.
Its last known location was over rural MS, and the resulting debris from the crash was found in LeFlore County, fewer than 100 miles from Jackson, the state's capital.
Fifteen marines and one navy sailor were killed, the US Marine Corps says.
The Marine Corps said that 16 service members died.
Another man borrowed Jones' phone to report that three bodies were thrown across U.S. Highway 82, which was approximately a mile from the original crash site.
People forced to evacuate homes after wildfires spread through California
The fire was one of several threatening homes around the state during a heat wave that has made it hard on firefighters. Santa Barbara officials sent alerts to residents and campers near Cachuma Lake to evacuate as the fire spread.
A Marine Corps spokeswoman at the Pentagon, Capt. Sarah Burns, said that one of the service's KC-130 aircraft had "experienced a mishap".
Equipment on the plane included small arms ammunition and personal weapons, the Marine Reserves said in a statement. Further details were not released.
President Donald Trump said on Twitter that the crash was heartbreaking. "(First Lady) Melania and I send our deepest condolences to all!"
Jones said the plan hit the ground behind some trees in the soybean field, and by the time he and others reached the crash site, fires were burning too intensely to approach the wreckage. Randle later told the Associated Press that the cause of the KC-130 refueling tanker's crash wasn't known as of Monday night and that the USMC confirmed that it was its plane but didn't state where the flight came from or where it was headed.
"Marine Plane crash in MS is heartbreaking".
Federal Bureau of Investigation spokesman Brett Carr told the New York Times that the agency was sending officials to the scene, but authorities did not believe foul play was involved.