Six volunteer firefighters injured after water tanker rollover

A group of six Rural Fire Service volunteer firefighters have been injured on the NSW south coast.

The crew were travelling in a water tanker when it rolled at around 11pm as they were battling the Clyde Mountain fire in Eurobodalla.

Two ambulance crews were called to the scene and assessed the six firies suffering from minor head injuries, lower back pain and neck pain, a NSW Ambulance told Yahoo News Australia.

Four were admitted to Bateman’s Bay Hospital overnight with possible spinal injuries, a hospital spokeswoman told Yahoo News Australia.

Two have since been discharged and all are in stable condition, she said.

The crash occurred just hours after three US firefighters died when their air tanker crashed while battling bushfires in southern NSW.

Investigators will on Friday begin piecing together the events that caused the C130 water tanker to crash in the Snowy Mountains on Thursday afternoon.

The plane, known as Zeus, was owned and operated by Canada-based company Coulson Aviation and contracted to the RFS.

The three firefighters - seconded to Australia from the US - died after the plane smashed into the ground 50km northeast of Cooma and exploded in a large fireball, NSW RFS commissioner Shane Fitzsimmons said.

The plane was located about 1.15pm on a private property at Peak View.

The three men were aged 42, 43 and 45, and Mr Fitzsimmons said they were experienced and trained in the use of the C130 tankers for firefighting.

The cause of the plane crash remains unclear.

Audio has emerged of the moment stunned ground staff called for help after witnessing the crash.

“Fire comms… message red speak to your captain. Message this is red,” the man on the ground says in the call to Rural Fire Service command.

The audio, aired on the Today show on Friday morning, briefly becomes inaudible before someone says: “Crashed.”

“Yeah fire comms... It's just a ball of flames... over,” the man finishes.

- with AAP

More to come.