About 140 firefighters are tackling a major fire at an industrial bakery in Wakefield, which is covering the area in thick black smoke.
The blaze at the Speedibake factory, close to Westgate Retail Park, started at about 13:30 GMT.
West Yorkshire Police said there were no reports of any injuries.
People living nearby have been told to shut all doors and windows and the wind is also causing smoke to blow towards the city centre, the force said.
Nicky Harley was going to the B&Q shop on the retail park when the fire broke out.
“As I approached the store I saw police officers in masks telling people to move back,” she said.
“There was heavy thick black smoke.”
She said she then walked over to a nearby supermarket and saw people with their hands over their mouths saying they felt light headed.
“I also felt faint and light headed,” she added.
“There is a McDonalds, a bingo hall and a cinema there too, so many people would have been affected.”
Several roads have been shut and drivers have been told to find alternative routes.
Some people on social media also reported hearing explosions coming from the factory.
Fire chiefs said the blaze had spread to about 75% of the ground floor of the building, with 140 firefighters from around the county on site.
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