There's a reduced service on the First Great Western line between Bristol and London Paddington.
Trains are being diverted via Newbury, and services are suspended between Cheltenham at Paddington, with replacement buses in place between Swindon and Didcot; Swindon and Gloucester; and Bath and Swindon.
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George Ford booted 24 points as Bath kept the pressure on Northampton at the top of the Premiership with a 39-16 win at rivals Gloucester.
West Country neighbours meet for first time this season at Kingsholm in Premiership.
The funeral of a mother and newborn baby found dead after going missing from a maternity hospital took place today.