Scotland to London rail services are experiencing major disruptions as a number of high-speed trains are taken out of service as a "precationary measure". 

The issue, initially reported yesterday, was the discovery of hairline cracks on a number of Class 800 series Hitachi trains used by several train companies including LNER.

The Azumas travel between Edinburgh, London, Leeds, York and Newcastle and were designed using 'Japanese bullet train technology'.

All Azuma trains are being investigated. 

LNER warned passengers not to travel today. 

In a statement on Twitter they said: "Customers are advised to not travel today and can use their tickets from today and yesterday (Saturday, May 8) up to and including Sunday May 16 with a new reservation."

The problem is being investigated by Hitachi.

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Great Western Railway (GWR), who also operate this model, have announced further potential cancellations going into next week.

ScotRail are also operating at a reduced level today as industrial action continues. 

Ticket examiners and conductors are involved in the strike action by rail union RMT over calls for a 50% increase in overtime payments for no additional hours worked.