UPDATED 5.38pm: A 12-year-old girl remains in hospital after being injured while helping her mum move stock on a farm near Te Awamutu.

The girl was hurt when a cow reacted adversely, and caused her to fall onto the tow bar of a trailer attached to a quad bike being driven by her mother.

The girl has neck and back injuries.

The girl was treated at the scene by ambulance staff, then flown to Waikato Hospital by the Waikato Westpac Rescue Helicopter.