Three members of Britain’s Royal Navy were killed in a training exercise when their helicopter exploded into “a ball of fire in the sky,” according to witnesses.

The Merlin Mk4 helicopter came down during a training mission in a field in Sourton, Southern England, at 3:45 a.m. Wednesday, with photos showing only the damaged tail amid the fully charred remains of the rest.

“I saw a ball of fire in the sky,” a witness who only gave her first name, Louise, told the Sun.

“It crashed into the field and then exploded. It was terrifying. I don’t think anyone could have survived that. It all happened so quickly.”

The helicopter — which can carry up to three crew members and 24 troops — was “pointing nose down towards the ground,” before the crash, Louise, 32, said.

Local resident Eddie Amhof, 81, told the BBC an “almighty flash of red lit up the sky” before the sound of the explosion reverberated through the rural West Devon village.

“We’re in an area where very little happens really apart from car smashes, but nothing disastrous like that,” he said.

The victims have not been identified, but UK Defence Secretary John Healey said they all “served with excellence and will be much missed.”

Catherine, Princess of Wales, who is the Commodore-in-Chief of the Royal Navy’s Fleet Air Arm, said she was left “saddened” by the losses.

“William and I hold their families and friends in our hearts at this very difficult time,” she wrote on social media.

The cause of the crash is being investigated.