A fleet of brand new train carriages were covered in graffiti while parked in a Tonbridge rail depot.

The 52 Class 777 coaches made by Swiss company Stadler were destined to Merseyrail in Liverpool as part of a £500m investment in the network.

The clean-up operation is likely to cost thousands of pounds.

British Transport Police said: ‘Officers were called to an area in Tonbridge at 12.21am on Saturday following reports of three youths graffiting. Officers quickly attended but the youths had left the area. Enquiries are ongoing."

A spokesman for Merseytravel said: “We are very disappointed that this has happened to one of our units that was being temporarily stored at the Tonbridge depot in Kent. This type of irresponsible behaviour will not be tolerated.

“The graffiti is now being removed at our Kirkdale depot at a cost of thousands of pounds. The trains will then be ready for testing on the Merseyrail network.

He added: "We also want to strongly remind graffiti artists that train depots are ‘live sites’ and can be extremely hazardous so please don’t put your lives at risk by trespassing.”

A picture of the vandalised train was shared by rail enthusiasts Railmen of Kent on Twitter.

A video showing the damaged carriages and a workman trying to clean off the paint was posted on the YouTube channel of Rail In Kent. It has already been seen 1,100 times.

It shows the yellow coaches covered in black, white, orange and purple spray paint and the words 'First Hit HSL'.

There is also a 'tag' clearly visible with the words 'Blud Spelt.'

The carriages were stopped in Kent on their way from a test track in Wildenrath, Germany and were due to leave the depot at 1.40pm on Monday. They are scheduled to start carrying passengers across Merseyside and parts of Lancashire and Cheshire in the autumn.

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