There's disruption on First Great Western services between Bristol Temple Meads and London Paddington and between Cheltenham Spa and London Paddington due to a person being hit by a train between Swindon and Didcot Parkway.
Trains may be delayed by up to an hour, and buses have been requested to run between Swindon and Reading.
Tickets are being accepted on CrossCountry and Virgin Trains services.
More top news
The blaze in the Greenbank area of the city happened on a street occupied by around 40 caravans.
People across the West Country have been reflecting on a spectacular royal wedding ceremony.
There could be some showers in the East later on.