A 12-year-old boy was airlifted to Alder Hey Children's Hospital after suffering serious facial injuries on a fairground ride in Poulton.
The youngster was treated by paramedics called to Fosters Funfair - held on the Cottam Hall playing fields as part of the town's gala celebrations - before being taken to the specialist Merseyside hospital by helicopter, police said.
He suffered a fractured eye socket and medics said he may need surgery, a spokesman said.
In a Facebook post, the boy's mum said he had an operation last night.
She added: "Police are involved and the ride has been impounded."
Police officers were called to the fair, off Blackpool Old Road, by the ambulance service shortly after 5pm yesterday.
An investigation into the cause of the accident was launched, and the ride was stopped 'immediately', the spokesman added.
Writing on Facebook, Ian Roberts said he was at the fair with his daughter when the boy fell 'while the ride [was] in motion'.
He said others on the ride screamed in horror after seeing his injuries.
More to follow