An accident is causing major queues at the Chowns Mill roundabout during Thursday's morning rush-hour.
Highways England traffic sensors show vehicles heading towards Wellingborough from the A14 along the A45 westbound from the A6 is stalled for three miles back to the Raunds roundabout.
Queues are also building eastbound on the A45 as emergency services deal with the incident.
Northamptonshire Police have said a van and a Ford KA were involved in the shunt at 7.55am but there are no reports of serious injures.
Highways England is currently part way through a £24million improvement scheme at Chowns Mill, set for completion later this year or in early 2022.