FIREFIGHTERS faced a tense wait yesterday as flames threatened to tear through a North-East factory.

Three crews responded to an emergency call to the Walkers Smiths Snack Foods crisp plant in Stephenson Road, Peterlee, County Durham, at 3.10pm, after reports of a huge deep fat fryer on fire.

Workers evacuated the building and fire officers had to wait until the factory's carbon dioxide fire extinguishing system kicked in and the temperature inside the vat had dropped to a safe level.

They moved in and put out the final flames at about 5pm.

The fire broke out in the vat, one of three production lines at the factory, which moves potato slivers on a conveyor belt through boiling oil.

A fire brigade spokesman said: "Some of the crisps got stuck on and were dragged round again, so were double or triple cooked and eventually caught fire. They ignited the peripheral oil underneath the machine.

"This caused the plant's automatic extinguishing system to operate, which controlled the flames.

"We had our foam lines in place for a worst-case scenario and used on-site employees to turn the system down, so we could extinguish the fire.

"The on-site personnel did everything we asked of them and we applaud them for that."

Extractor fans inside the building ensured that there was no major internal smoke damage.