Rush-hour commuters have been urged to avoid a section of the M1 in Nottinghamshire after a lorry pile-up in the early hours of Thursday.
Five heavy goods vehicles were involved in the accident between junctions 25 and 26, just north of Trowell Services on the northbound carriageway.
Nottinghamshire Police said the road has been closed while officers carry out inquiries at the scene and to allow the vehicles to be recovered.
One driver was seriously injured after he became trapped in his vehicle and had to be cut out by the fire service. He has been taken to hospital for treatment.
Another driver also had to be cut free but is not said to be badly hurt.
The road is expected to be closed for some time and motorists are strongly advised to take other routes until further notice.
The southbound carriageway is unaffected.