Firefighters are tackling a blaze at Stanlow Oil Refinery near Ellesmere Port.
Emergency services have received several calls reporting a huge ball of black smoke coming from the refinery from 2.16pm on Wednesday.
Cheshire Fire and Rescue Service confirmed it has sent six engines to the scene.
Bromborough firm Helukabel UK captured the Stanlow Oil Refinery 'explosion' on its CCTV camera
The fire at the Stanlow Oil Refinery, Ellesmere Port. Picture: Phil Owen
Black smoke seen from Cheshire Oaks. Picture: Twitter / John Edwards
Essar, which runs the refinery, released a statement at 4.45pm today.
A spokesman said: “Earlier this afternoon a fire occurred at the SHOP chemical plant. Both the site emergency services and Cheshire County Fire Service are in attendance to deal with the incident.
"All personnel have been accounted for. Refinery operations at Stanlow remain unaffected.”
One of the two incidents reported at the site is controlled burning, while firefighters are "fully investigating" the other.
A spokesperson for Cheshire Fire and Rescue Service said: "All staff have been accounted for and have been evacuated.
"Crews are working with onsite firefighters to extinguish the fire which is believed to be in a manufacturing building within the plant."
Shoppers at nearby Cheshire Oaks took to social media to post pictures of black smoke pouring into the air.
Thick smoke pouring from oil refinery. Picture: Twitter / @TheGalleyEP
The fire at the Stanlow Oil Refinery, Ellesmere Port. Picture: Twitter / @thomodavie
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