Police have released CCTV following a large fire in Malvern on Tuesday.
The blaze broke out on the disused industrial estate in St Andrews Road.
Officers say the fire is being investigated as arson not endangering life.
They are keen to trace a group of five people who were caught on CCTV in the area at the time of the incident.
Anyone with information is asked to call West Mercia Police on 101.
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