The M25 motorway, a major transport artery in the United Kingdom, has been closed in both directions between junctions 22 and 21A near St Albans due to a significant warehouse fire. Hertfordshire Fire and Rescue Service is on the scene, with 15 crews battling the blaze at a warehouse located in Ventura Park, Old Parkbury Lane, Colney Street.

National Highways reported that the closure is in place due to smoke affecting the carriageway and a heightened risk of a "secondary explosion, along with smoke and debris affecting the carriageway." Authorities are advising the public to keep doors and windows closed and to avoid the area. Hertfordshire Police confirmed the road closure is a direct result of the smoke emanating from the warehouse fire. Road closures have also been implemented on Colney Street and Old Parkbury Lane.

The proximity of the warehouse to the railway line has led to Network Rail having a representative on site, liaising with the fire service. Traffic is experiencing delays of approximately 60 minutes in both directions approaching the affected section of the M25. Drivers are urged to allow for substantial extra travel time and to seek alternative routes. A large plume of smoke by the M25 motorway, with cars on the road across a bridge. Trees are to the left and all around the road.