Watch: Thick smoke at retail park from Dunelm fire
Video posted on social media showed thick smoke drifting across a retail park from a fire at a Dunelm store.
Emergency services were called to St James Retail Park, off Towcester Road in Northampton, at about 15:00 BST on Saturday.
Police believed the fire - which spread to the Pets at Home store - was started deliberately and have arrested three people.
They said neighbouring businesses at the park would be open as normal on Monday, but a small section of the car park would remain shut while crews tackled remaining hotspots, external.
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