Emergency services are tackling a fire at a gas conversion garage in Darlington.
There are also reports of explosion at the building on Cleveland industrial estate in the Albert Hill area.
The air ambulance is taking one casualty to Newcastle's RVI.
He's believed to have arm and head injuries.
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Chancellor George Osborne will seek to reassure financial markets on Monday morning following Britain's decision to leave the EU.
Eight crew members had to be rescued from a fishing boat after it started sinking a mile off the coast of Sunderland.
Drivers travelling north or southbound on the A1 near Newcastle and Gateshead are advised to expect delays until Wednesday morning.