A rubber fire which has sent clouds of thick black smoke across Carlisle could continue for days, firefighters say.
Firefighters are using foam to put out the fire
The fire at a warehouse on the Kingmoor Park estate on Monday destroyed £750,000 worth of rubber destined for the Pirelli tyre factory in the city.
Fire crews from Scotland have been drafted in to help tackle the blaze.
A special foam compressor from Glasgow was also brought onto the site, since the use of water produces a toxic run-off which could affect rivers.
Cumbria's assistant chief fire officer Dave Keevil said: "This is a very difficult fire situation which could continue for days and continue to produce black smoke.
"We are inhibited in the use of water because that will produce a toxic water run-off which has the potential to get into the water courses."
Emergency services earlier warned people to stay away from the area, which is about two miles outside Carlisle.
People were advised to close their doors and windows, although fire officers said the risk to residents at this stage is very low.