Emergency services have rushed to an incident on the railway line near Swindon as trains are delayed and cancelled.
The incident, which was first reported just after 5pm on the line between Reading and Didcot, has sparked a huge emergency response.
Trains running between Reading and Swindon/Oxford have all been affected, with most trains on this line either delayed or cancelled.
Although the incident has now been resolved and the lines have reopened, National Rail says that disruption can still be expected until 7pm tonight (September 24) and delays will be up to 70 minutes.
Other services affected by the incident include the CrossCountry service between Bournemouth and Manchester Piccadilly and between Reading and Newcastle.
Great Western Railway services between London Paddington and Didcot Parkway, Oxford, Banbury, Cheltenham Spa, Worcester Foregate Street, Bristol Parkway, Bristol Temple Meads, Weston-super-Mare, Taunton, Great Malvern, Hereford, Cardiff Central, Swansea and Carmarthen are also affected.
A spokesperson for National Rail said: "Following the emergency services dealing with an incident between Reading and Didcot Parkway all lines have reopened.
"But as service recovers, trains may still be cancelled, revised, diverted or delayed by up to 70 minutes.
"Major disruption is expected until 19:00."
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