THE A45 near Harpole has been closed due to a spill of oil and bleach.
At shortly after 1.05am, an articulated lorry overturned and went through the central reservation, shedding a hazardous chemical onto the road.
The fire service, police and Environment Agency are on the scene trying to contain the spill and prevent it from polluting the nearby River Nene.
The driver of the lorry, a 29-year-old man, is not believed to be seriously injured but was checked over by an ambulance team.
The Weedon Road is closed in both directions and drivers are warned to expect delays and extra traffic on alternative routes.
Work is being carried out to recover the lorry and clean up the spillage and it is hoped that the road will be re-opened by lunchtime or early afternoon.