Millions of rail passengers suffered miserable journeys this morning after a series of problems led to long delays on major routes.
The difficulties included hold-ups in and out of Victoria, King's Cross, Moorgate and Fenchurch Street stations in London.
Problems at Victoria came after smoke was seen pouring from the engine of an empty Gatwick Express train.
The station was evacuated and, although it later reopened, long delays persisted through the morning, with some London-bound rush-hour travellers held up outside Victoria for up to an hour.
A broken-down train at Angmering in West Sussex meant buses had to replace trains between Worthing and Littlehampton.
Nearby, a signalling problem at Chichester led to delays between Barnham and Havant in Hampshire.
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Tuesday afternoon's weather for the west of the region
Tuesday afternoon's weather for the east of the region