There is disruption on First Great Western between Worcester Shrub Hill and Swindon, and between Worcester Shrub Hill and Oxford because of a derailed train.
Some lines are now blocked as the train is re-railed which could take up until 2.30pm.
Replacement buses are running between Worchester Shrub Hill and Cheltenham and journeys will be delayed by up to half an hour.
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A man described as a paranoid schizophrenic who killed his parents in Swindon, has been sent to a secure hospital for life.
Wednesday afternoon's weather for the east of the region
Wednesday afternoon's weather for the west of the region