Thieves ram-raided an industrial unit before escaping on motorbikes and causing a major fire which brought part of Corby to a rush-hour standstill.
Police investigating the blaze which engulfed Cartell UK and KCS Group in Shelton Road in the early hours of Tuesday have revealed the incident is being treated as suspected arson.
The fire caused a huge black smoke plume to rise above the town.
Steel Road was sealed off preventing people from getting to work on the Willowbrook East industrial estate and the surrounding areas while firefighters battled to bring the flames under control.
About 70 firefighters and 10 engines were at the scene at the height of the blaze, which started between 5.15am and 5.40am.
Small gas canisters could be heard exploding. No-one was injured.
A police spokesman said yesterday: “We can now confirm that the vehicle used in the suspected arson was a Range Rover which had been stolen from Caldecott in Leicestershire.
“The vehicle was used to force entry into Cartell Limited. The offenders then forced entry from Cartell into adjoining business KCS Group.
“We can also confirm that two suspects left the scene on motorbikes stolen from KCS.”
KCS Group and Cartell UK declined to comment on the blaze.
Police issued a witness appeal yesterday.
The police spokesman added: “We are not aware whether the incident is linked to any other ram raids but investigations are continuing.”
Fire crews left the scene at 8pm on Wednesday and were due to return to conduct after-fire inspections at the site.
Witnesses or anyone with information should call police on 101 or Crimestoppers anonymously on 0800 555111.
No-one had been arrested in connection with the incident at the time of going to press yesterday.