The mainline railway into South Wales has been shut because of an emergency.
There are no Great Western Railway or CrossCountry trains running into or out of south Wales following the incident between Severn Tunnel Junction and Newport.
Emergency services are attending the incident and all llines are blocked at Caldicot.
A spokesman from Cross Country Trains said: "Due to emergency services dealing with an incident between Severn Tunnel Junction and Newport (South Wales), all lines are blocked."
On its website, Great Western Railway says that disruption is expected until the end of the day. It's affecting all trains between Cardiff and Bristol on the mainline to London.
British Transport Police have been contacted for comment
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