The M1 in Northamptonshire remains closed northbound between junctions 15a and 18 after a lorry jack-knifed this morning at about 2am, causing a large diesel spillage.
The Highways Agency is carrying out major repairs to the carriageway following the diesel spillage and the road is now expected to remain closed until around 8pm this evening.
A diversion is in place taking traffic off at junction 15a, along the A43 and A5, to junction 18.
The northbound slip road at junction 15 is also closed.
Motorists are advised to find an alternative route if they are planning to travel northbound between junctions 15 and 18.
There is significant congestion in the area and motorists are being advised to leave plenty of time for their journey.