The A1 is closed in Peterborough and Lincolnshire this morning.
A truck has hit overturned, shedding sulphuric acid.
The road is closed in both directions between the Colsterworth Services junction and the A606 Rutland Water turn off.
Cambridgeshire police said this morning the road was closed at Wothorpe, while Lincolnshire police said the road was closed at Colsterworth. However, it is now clear those were the same incident and not separate as first believed.