Firefighters are tackling a large fire at the Milburngate development in Durham City.
Durham and Darlington Fire and Rescue Service said that five crews are currently in attendance but said there were no reports of an explosion.
A spokesperson said: "There are currently eight crews at scene of a fire at the Milburngate development in Durham City.
"We would like to confirm there are no reports of an explosion and our crews are dealing with large fire in the construction site.
"Our colleagues from Durham Constabulary have closed the surrounding roads while our crews bring the fire under control. One person has been treated for smoke inhalation at the scene."
Local residents have been advised to close their windows and doors and to avoid travelling into the city centre.
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