A UK tech firm which supplies WiFi and CCTV services for trains across the world is set to be bought out by Alstom.

Newcastle-headquartered Nomad Digital has offices in the UK, Netherlands, Germany, Portugal, Canada, Australia, and the US.

Founded in 2002 by Dr Nigel Wallbridge and Graeme Lowdon, it now employs around 230 people.

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The purchase should be completed early 2017, and the pair said they share a vision to make the 'digital train' a reality.

Alstom has signed a purchase agreement to buy Nomad from Amadeus Capital Partners, SEB Venture Capital and Deutsche Telekom Strategic Investments, among others.

Andrew Taylor, Nomad group chief executive, said: "Alstom's acquisition of Nomad is fabulous news for our staff, our customers and our partners around the world."