The main route between Northampton and Kettering is expected to remain closed for several hours after a serious collision involving a car and an HGV on Monday (June 6).
Police have shut the A43 at the Mawsley roundabout in both directions as far as the Hannington turn.
All the emergency services are at the scene following the crash at around 9.20am. An air ambulance also landed close by as firefighters battled to free the trapped occupant of one of the vehicles.
The A43 is closed both ways between Northampton and Kettering on Monday (June 6) following a serious collision near the Mawsley roundabout
A spokesman for Northamptonshire Police said the road is expected to remain closed for some time while investigation work is completed.