Delays of up to 30 minutes on East Coast between Kings Cross and Doncaster due to signalling problem at Peterborough.
Mainly affecting northbound services.
Trains are running at reduced speed through the affected area, resulting in delays.
There is no estimate for a normal service.
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He has agreed a two-year contract at St. James' Park and becomes the tenth new face in the Magpies' first team squad this summer.
On the back of three consecutive Championship wins, the Magpies sit fourth, poised to move into the automatic promotion places.
Callum Young, who will now be 23, was last seen on August 27 last year at his home in Hylton Road.