ATLANTA — Sixteen troops died when a Marine Corps transport plane crashed in the Mississippi Delta on Monday, the military said early Tuesday.

In a brief statement, the Marines said the flight, involving a KC-130 transport plane, had originated at an air station at Cherry Point, N.C., near the Outer Banks. The Marines did not identify the dead or their service branch affiliations.

“While the details of this incident are being investigated, our focus remains on providing the necessary resources and support to the family and friends of these service members as they go through this extremely difficult time,” the statement said.

Military and local officials said the cause of the crash was unclear.

The transport plane, the military said, crashed at about 4 p.m. on Monday in Leflore County, Miss., about two hours north of Jackson. By late Monday, with a debris field spread over several miles of Mississippi Delta farmland, the local authorities announced that they were recovering bodies.

Edna Beavers was trimming the grass outside her house in Itta Bena, Miss., on Monday afternoon when, she said, she glanced up and saw a huge plume of black smoke rising from a soybean field about a mile away. “I was like, ‘Oh my God,’” Ms. Beavers, 68, said in an interview Monday night.

Ms. Beavers said the military plane crashed along County Road 547, a dirt road that connects acres of farmland between Itta Bena and Moorhead. There are few homes along the road, she said. A military jet later circled overhead, she said.

“That is a sad situation there,” she said.

President Trump, in a tweet on Tuesday, called the crash “heartbreaking.”

“Melania and I send our deepest condolences to all!” the president wrote, referring to his wife.