Turkey on Wednesday said 20 of its soldiers were killed when a military transport plane crashed in Georgia, with all but one of the bodies recovered, marking the NATO member's deadliest military incident since 2020.

The C-130 cargo aircraft left Azerbaijan for Turkey and crashed in Georgia on Tuesday, leaving chunks of twisted metal strewn across a grassy knoll.

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Ankara has not provided a reason for the crash, but said Turkish and Georgian authorities had started investigations at the site.

In a live speech, Turkish President Tayyip Erdogan said: "Our plane's black box has been found, and inspections have begun. We have recovered the remains of 19 of our martyrs. Our search for the remains of the last martyr continues."

WIDELY USED TACTICAL AIRCRAFT

Footage from the site near the border with Azerbaijan showed ambulances, firetrucks and army vehicles in the area around the burned fuselage, with search-and-rescue teams scanning the grounds.

Ankara said it was closely coordinating with Azerbaijan and Georgia on the probe.

U.S. defence firm Lockheed Martin, which makes the C-130 Hercules, said it was committed to helping the investigation.

The C-130 Hercules, which is used widely by air forces around the world, is a four-engine turboprop military transport aircraft capable of operating from unprepared runways.

Its versatile airframe allows for cargo, troop and equipment transport, airborne assault and reconnaissance missions, making it a mainstay tactical airlifter for many militaries.

INITIAL EVIDENCE SUGGESTS ACCIDENT

Unverified social media videos on Tuesday showed the plane breaking apart in the air and then corkscrewing toward the earth in a blaze.

Some analysts have said footage and images indicate the plane broke apart mid-flight, adding that Turkey's fleet of C-130s is old and in need of renewal, despite the aircraft's reliability.

"The footage appears to show the tail section separating in-flight and fuel streaming from the wingtip valves, suggesting the crew may have been dumping fuel for an emergency landing," said Jarrod Phillips, a former U.S. Air Force C-130 specialist.

FlightRadar24 and two Turkish defence analysts said the plane that crashed was 57 years old and had entered the Turkish Air Force in 2010.

Last month, the Turkish Defence Ministry unveiled an agreement with Britain to procure 12 C-130J aircraft. The planes will undergo maintenance and modernisation in Britain and later begin their service for Turkey, it said.

In an accident in 2017, a U.S. KC-130T Hercules plane crashed in Mississippi, killing all 16 people on board. Witness accounts at the time said the aircraft came down while on fire in a flat spin. The incident report said the cause was improper repairs on a corroded propeller blade, leading to a failure.

Tuesday's crash was Turkey's deadliest military incident since February 2020, when Russian-backed Syrian forces killed 33 Turkish troops in Idlib, northwest Syria, where Turkey was supporting rebels looking to oust the Syrian government.