AN investigation is underway after a track worker suffered serious injuries after being hit by am 80mph train in Redhill.
The Rail Accident Investigation Branch (RAIB) is looking into how a Network Rail employee was struck by a passenger train on June 24.
The incident occurred at around 10.40am when the man was supervising a group of 11 workers carrying out repairs to the Up Quarry Line between the Redhill Tunnel and Quarry Tunnel.
He was struck by a passenger train travelling at 80mph from Gatwick Airport to Redhill.
The incident brought the Southern Rail network to a standstill while the man was treated.
RAIB says he suffered serious injuries.
A statement said: "RAIB's investigation will consider the sequence of events and factors that may have led to the accident, and identify any safety lessons.
"RAIB's investigation is independent of any investigations by the safety authority or the police. RAIB will publish its findings at the conclusion of the investigation."