An ambulance spokeswoman said paramedics responded to reports of a fireworks explosion on Milbrulong Road, Lockhart, in south-western NSW's Riverina region, about 12.10am on Wednesday.

She said two patients were taken to Wagga Wagga Base Hospital but Strong was reported to be the more badly hurt. He suffered a serious leg injury as well as chest and facial injuries.

He was flown to hospital by helicopter and then by plane to Sydney, where he was admitted to the burns unit of St George Hospital.

"His left leg around his thigh is the worst part," his father Lyndon said.

"He will pull through, no worries at all."

Strong, 22, made a name for himself in the motocross arena, rising from performing as a youth at the Lockhart Show to bagging a swag of medals on the world stage. The reigning X Games Best Trick gold medallist has ridden for the action sports show Nitro Circus.

A 24-year-old man suffered burns to his face and large cuts above both eyes after a fireworks accident at a property at Waukivory, north of Newcastle, at 10.37pm on Tuesday, a NSW Ambulance spokeswoman said.

The victim was taken to Gloucester Soldiers' Memorial Hospital, then flown to John Hunter Hospital in a serious condition.

He underwent emergency surgery on Wednesday amid fears that he could lose the sight in both eyes.