(ABC NEWS) -- A military transport plane crashed in Mississippi on Monday, killing at least 16 service members, the Marine Forces Reserve has confirmed.

The Marine Corps KC-130 aircraft crashed in Leflore County, Mississippi -- located about 85 miles north of Jackson -- at around 4 p.m. local time, according to the Mississippi Emergency Management Agency.

The flight took off from Marine Corps Air Station Cherry Point, N.C., the Marine Forces Reserve said in a statement.

The plane vanished from air traffic control radar somewhere over Mississippi, the statement continued.

The Marine Forces Reserve said that cause of the crash is still unknown, and the incident is currently under investigation. They are withholding the names of the deceased in order to allow more time for loved ones to be notified.

"While the details of the 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 from the Marine Forces Reserve said. "More information will be released as it becomes available."

Witnesses described hearing a loud “crackling” noise around the time of the plane crash.

Andy Jones, a local farmer, said he heard a loud boom and described watching the aircraft twirling through the air before falling down.

"[The plane] was spinning down," Jones told The Associated Press late Monday.

Speaking at a press conference late Monday, Leflore County Emergency Management Director Fred Randle also offered no explanation for the crash and stressed that the situation was still under investigation.

The FBI was also on the scene Monday's presser, and Randle said that the EMA would address the public about the crash again Tuesday.

The Marine Corps, which said it operated the plane, originally announced the crash via Twitter at about 8:30 p.m. ET.

"A USMC KC-130 experienced a mishap the evening of July 10," said Capt. Sarah Burns, a Marine Corps spokesperson said earlier. "Further information will be passed as available."

President Donald Trump tweeted about the crash, calling it “heartbreaking.”

“Marine Plane crash in Mississippi is heartbreaking. Melania and I send our deepest condolences to all!” Trump wrote.

The Associated Press contributed to this report.