Thanks again to all those who have posted updates on this rather sorry situation in the Great Western area this evening.

To summarize - from First Great Western JourneyCheck:
Line problem: between Swindon and Didcot Parkway.
Following a person hit by a train between Swindon and Didcot Parkway all lines have now reopened.
Train services running through these stations are returning to normal. Normal services will be provided as soon as possible.
Following a person hit by a train in the South Marston area lines have reopened however there will now be residual delays until end of service.
Cross Country services are conveying passengers via any reasonable route until further notice. Arrangements have been made for First Great Western rail tickets to be accepted for these journeys.
Arrangements previously made with Virgin Trains to convey passengers have now been withdrawn.
Message Received: 24/05/2013 19:59
Train Cancellation
20:48 Cheltenham Spa to Bristol Temple Meads due 22:11
This train will be cancelled. This is due to an obstruction on the line.
Message Received: 24/05/2013 16:55
Other Train Service Updates
16:28 Swansea to London Paddington due 19:33
This train has been delayed at Swindon and is now 85 minutes late. This is due to a person hit by a train earlier.
Message Received: 24/05/2013 19:57
17:10 Weston-Super-Mare to London Paddington due 19:16
This train will be delayed at Reading and is expected to be 56 minutes late. This train will be diverted between Swindon and Reading. This train will no longer call at Didcot Parkway. This is due to a person hit by a train.
Message Received: 24/05/2013 18:44
17:28 Worcester Foregate Street to London Paddington due 20:06
This train will call additionally at Didcot Parkway. This is due to a person hit by a train.
Message Received: 24/05/2013 18:47
17:28 Swansea to London Paddington due 20:37
This train will be diverted from Bristol Parkway. This train will be terminated at Bristol Temple Meads. This train will call additionally at Bristol Temple Meads. This train will no longer call at Swindon, Didcot Parkway, Reading and London Paddington. This is due to a person hit by a train.
Message Received: 24/05/2013 19:14
17:30 London Paddington to Taunton due 20:23
This train will be delayed at Bath Spa and is expected to be 6 minutes late. This train will be diverted between Reading and Bath Spa. This train will no longer call at Didcot Parkway, Swindon and Chippenham. This is due to a person hit by a train.
Message Received: 24/05/2013 18:38
17:39 Cheltenham Spa to Southampton Central due 20:48
This train will be delayed at Gloucester. This train has started from Gloucester, terminated at Swindon and restarted from Westbury. This train will no longer call at Cheltenham Spa, Chippenham, Melksham and Trowbridge. This is due to an obstruction on the line.
Message Received: 24/05/2013 18:50
17:45 London Paddington to Swansea due 20:47
This train has been delayed at Reading and is now 25 minutes late. This is due to a person hit by a train.
Message Received: 24/05/2013 19:35
17:50 London Paddington to Worcester Shrub Hill due 20:05
This train has been delayed and is now 37 minutes late from Oxford. This train will be diverted from Worcester Shrub Hill. This train will be terminated at Worcester Foregate Street. This train will call additionally at Didcot Parkway and Worcester Foregate Street. This is due to a person hit by a train.
Message Received: 24/05/2013 19:43
17:55 Cardiff Central to London Paddington due 19:54
This train is being delayed at Swindon and is now expected to be 60 minutes late. This is due to a person hit by a train earlier.
Message Received: 24/05/2013 19:58
18:00 London Paddington to Bristol Temple Meads due 19:43
This train has been delayed at Reading and is now 73 minutes late. This is due to a person hit by a train.
Message Received: 24/05/2013
19:43 18:15 London Paddington to Swansea due 21:19
This train has been delayed from London Paddington and is now 73 minutes late. This is due to a person hit by a train.
Message Received: 24/05/2013 19:31
18:22 London Paddington to Hereford due 21:34
This train will call additionally at Didcot Parkway. This is due to a person hit by a train.
Message Received: 24/05/2013 19:08
18:30 London Paddington to Weston-Super-Mare due 20:53
This train will be delayed at Bath Spa and is expected to be 6 minutes late. This train will be diverted between Reading and Bath Spa. This train will no longer call at Didcot Parkway, Swindon and Chippenham. This is due to a person hit by a train.
Message Received: 24/05/2013 19:13
18:45 London Paddington to Swansea due 21:49
This train has been delayed from London Paddington and is now 46 minutes late. This is due to a person hit by a train.
Message Received: 24/05/2013 19:33
19:12 Reading to Newbury due 19:44
This train has been delayed at Reading West and is now 21 minutes late. This is due to a person hit by a train.
Message Received: 24/05/2013 19:36
19:12 London Paddington to Swansea due 22:21
This train has been delayed from London Paddington and is now 24 minutes late. This is due to a person hit by a train.
Message Received: 24/05/2013 19:39
20:01 Cheltenham Spa to Swindon due 21:03
This train will be started from Gloucester. This train will no longer call at Cheltenham Spa. This is due to an obstruction on the line earlier.
Message Received: 24/05/2013 19:35
21:15 Great Malvern to Bristol Temple Meads due 23:19
This train will call additionally at Cam & Dursley and Yate. This is due to an obstruction on the line earlier.
Message Received: 24/05/2013 20:04
... and from
the BBC:
Biker dies and M4 eastbound closed on second Severn Crossing
Five lanes of the crossing over the Severn were shut to deal with the fatal crashA motorcyclist has died in a crash on the second Severn Crossing, which has closed the M4 eastbound.
The man was declared dead at the scene following the alert at around 17:50 BST on Friday, said Gwent Police.
The eastbound crossing is closed at junction 23 for the M48 but the two westbound lanes of the bridge have now reopened.
Traffic was reported to be tailing back to the Coldra roundabout. It was being diverted along the old Severn Bridge.
However, the alternative M48 route is restricted to one lane due to high winds.
Two westbound lanes were shut so that emergency services could reach the scene. There was stop-start traffic into south Wales reported for 12 miles.
The eastbound carriageways remains closed for accident investigation work.