One person has died and another was seriously injured at a motocross event in County Durham.
The male rider, who has not been named, came off his bike at the privately-run event at Low Hardwick Farm, near Sedgefield, at about 13:00 BST.
He was taken to hospital in Middlesbrough but was confirmed dead shortly before arrival, police said.
A woman rider in her early 30s suffered serious injuries about an hour later at which point the event was closed.
A spokesman for Durham Police said: “We took the decision on safety grounds to close down the privately-run event, which involved around 100 participants and 300 spectators.
“We understand the formal investigation is likely to be led by the local authority, but we are carrying out initial inquiries into the circumstances.
“With two very serious incidents within little more than an hour, we felt there was little choice but to bring the event to a close.”
The site is regularly used for motocross and quad bike events.
No-one from the organisers has so far been available for comment.