THE head of Oxley police said more patients had been released from hospitals on Sunday as investigators try and work out what caused the out-of-control demolition derby car to plough into a Walcha crowd.

Oxley detectives and local police were back at the scene of the crash at the Walcha Showground on Sunday as part of the police probe into Saturday night's horrific crowd crash.

See more coverage: Nurse hailed for helping 13 injured in 'freak accident' at Walcha derby

Oxley Police Superintendent Dave Cooper told the Leader 13 men and women had been injured.

"It was a challenging incident because of the multiple injuries, and it's a small community, and add on top of that some bad weather," he said on Sunday.

"It was a very challenging scene but the first responders were absolutely a

See Full Page