SEMILONG FIRE: Police now believe Northampton power station blaze was ARSON
Detectives issue description of man seen in the area when blaze started at electricity substation
Detectives now believe an arsonist started the blaze which destroyed two 11,000-volt electricty substations in Northampton.
Investigators from police and Northamptonshire Fire & Rescue initially indicated the cause of Thursday night's fire was being put down to "an accidental electrical fire."
But officers today confirmed they now suspect it was the result of an arson attack and issued a description of a man seen in the area of Semilong, between 9pm and 10.20pm, at the time the blaze started.
A Northamptonshire Police spokesman confirmed: "The fire was originally thought to have been caused by a fault.
"However following further investigations, it is now suspected the fire was started deliberately.
"Officers investigating this incident would like to speak to a white male with dark hair and dressed in dark clothing who was seen in the area between the stated times."
Anyone with information or who may have witnessed the incident can call on 101 using reference number 21000207645, or contact Crimestoppers anonymously on 0800 555 111.
The fire started ripped through the substations in Semilong Road, next to the Co-op shop and in front of Alliston Court flats.
A dozen residents had to be evacuated as four crews of firefighters tackled the blaze into the early hours of Friday morning.
Local business were forced to close and thousands of homes in the NN1 and NN2 postcodes were left without electricity, some for up to a day while repairs were carried out.