A fierce blaze which destroyed part of a former crisps factory in Bradford was arson.

Specialist investigators yesterday concluded it was started deliberately after spending almost two days scouring the damage caused to the former Seabrook site in Allerton Road, Allerton.

The fire, described by barber Gerardo Chirola, 74, whose business adjoins the factory, as “like a volcano”, destroyed the third floor and roof of the derelict building on Monday evening.

Mr Chirola’s shop was also badly damaged leaving him fearing for the future of his business.

About 30 firefighters from six stations – Fairweather Green, Bradford, Illingworth, Bingley, Odsal and Shipley – were called to the scene shortly before 9.45pm on Monday and spent two hours putting it out. Some fire crews were on the scene until 5am the following day.

Now, police are appealing for people who saw anyone acting suspiciously in the area around the factory at the time to come forward.

Detective Sergeant Ken Robinson, of Bradford District CID, said: “We can confirm we are investigating a fire at a disused factory in Allerton Road, Bradford, which occurred just before 10pm on Monday.

“We would like to speak to anyone who might have seen someone acting suspiciously in the area leading up to that time or shortly after that time, as well as anyone who might have any information as to how the blaze started.”

A spokesman for West Yorkshire Fire and Rescue Service said: “Following a fire investigation the fire is believed to have started through deliberate ignition.”

Seabrook Crisps declined to comment on the cost of the damage caused, how it might affect the future sale of the site, or if the company was providing any assistance to Mr Chirola.