Crews from the Tyne and Wear Fire and Rescue were called to Egger chipboard manufacturing plant in Hexham at 10.30 last night.
Around 60 fire-fighters were involved and they were on the scene until around 6am this morning.
A 200 metre cordon was put in place, but has now been lifted.
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It happened around 10.25am on Sunday morning 18 February.
This double signing announcement comes after the news that French centre Maxime Mermoz will join the Falcons next season
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