Paddington station: Evening rush hour disruption expected
Rail passengers face disruption during the evening rush hour amid ongoing delays caused by damaged power cables.
There have been delays and cancellations to key routes in and out of London Paddington station throughout Wednesday.
Network Rail said disruption was due to last for the rest of the day and warned that services could still be affected on Thursday morning.
Great Western Railway has urged people to "only travel if necessary".
About 500m of overhead cables were "severely" damaged during a Hitachi train test run on Tuesday night.
As a result, services between Paddington and Slough, and Paddington and Heathrow Airport, had to be suspended.
The disruption affected passengers as far as south-west Wales, Bristol, Exeter, Plymouth and Penzance, according to Great Western Railway.
Check before travelling
Trains began running again around midday, but rail operators Great Western Railway, TfL Rail and Heathrow Express insisted services would be "limited" for the rest of the day.
Network Rail said engineers would begin to install new wires at 21:15 BST, but a spokesman said the "extent of the damage" meant the repairs "won't be completed in one night".
He added: "While services on Thursday morning will be significantly improved, there may still be some disruption.
"We advise passengers to continue to check with train operators before travelling."
A Hitachi spokesman explained the company was holding "a full and thorough investigation" to identify the cause of the damage.
The train had not yet been handed over to GWR, but was due to enter service on its Devon and Cornwall route.
The fault comes weeks after hundreds of passengers were stranded for six hours in September when a similar train built by Hitachi for GWR broke down just north of Exeter.
GWR said the incidents were unrelated.