What is believe to be a barn fire on South Brink near Wisbech is causing traffic problems along the busy A47 thanks to heavy black smoke drifting across the road.
Six fire crews with more than 25 firefighters are currently tackling a major farm fire on South Brink near Wisbech.
A spokesman for Cambs Fire and Rescue, confirmed, they were called at around 10.50am to the blaze which is affecting traffic along the nearby A47 because of the smoke it is generating is blowing across the carriageway.
The spokesman said the fire is in two farm buildings measuring approximately 50m by 100m and firefighters are wearing breathing apparatus and are using hose reels and jets to try to bring the blaze under control.
Drivers have been reporting the A47 was becoming congested because vehicles were forced to slow down due to poor visibility as a result of the smoke.
One eye witness told the Citizen he could barely see the road ahead because the smoke is so dense.
Another reported via social media that fire crews are now on the scene of the blaze.