There's disruption on First Great Western trains between London Paddington and Bristol Temple Meads due to a trespass incident at Swindon.
It's affecting all services through Swindon. Trains may be delayed or cancelled due to congestion through the area.
Journey times may be extended by up to 45 minutes until at least 5pm.
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Friday should start off nicely with lots of bright spells and only the odd shower. The afternoon will be warm with heavy rain in places