All passengers have been evacuated from a train between Worthing and Brighton after reports of smoke, Southern Rail has confirmed,.
According to Southern, train crew on board a Portsmouth & Southsea to Brighton service reported smoke emerging from the train, and has been 'taken out of passenger service for safety reasons'.
The smoke is believed to have come from an electrical fault, and passengers were evacuated at Shoreham.
A spokesman added: "All passengers have safely been evacuated from this train, and control and stations teams are in the process of arranging onward travel for those on board.
"During this time, the line towards Brighton currently remains blocked whilst the emergency services and Network Rail carry out necessary investigations.
"Due to the complexity of the situation, the train involved is unable to proceed and requires a rescue train to assist with the removal process.
"The rescue train is currently on site and railway response teams are working on the joining and attaching procedure. Southern expect to have the lines reopen shortly."
Southern said disruption is expected until 10pm.