From the BBC:
"On 28 July, 1958, a fire started in the electrical wiring of a Central line train between Shepherd's Bush and Holland Park station in west London, with most of the passengers suffering from smoke inhalation and one person later dying from breathing the fumes. Electrical arcing in power cables at the rear of the first carriage had produced an electrical arc which produced a torch-like flame, which blistered and melted the paint and other materials to produce acrid fumes. The current to the tracks was soon removed, and passengers had to be detrained towards both Shepherd's Bush and Holland Park.
"A similar incident occurred two years later on 12 August, 1960 when a fire started in the front carriage of a train between Redbridge and Gants Hill for the same reason. Fortunately no one was killed as the train was only partially full, though a few dozen people were taken to hospital. Precautions recommended after the Holland Park fire meant that the driver's cab had been insulated from the point where the arcing occurred, probably saving the driver's life. Meanwhile, this second accident led to further attempts to improve safety, with most of the 1938 tube stock which had the same type of wiring being altered or decommissioned soon afterwards."
