A serious collision closed the M1 Northbound in Milton Keynes earlier.
Highways England said the road was closed between J13 and J14 northbound with fire crews in attendance.
The closure was in place from 7pm on Monday until 6am on Tuesday.
The road has now re-opened.
The collision involved a car and a lorry.
Two fire appliances and crews from Broughton, one from Newport Pagnell, one from Woburn, one from Kempston and an officer attended.
No-one was trapped.
About 700 litres of diesel was spilled.
Firefighters used a dry powder extinguisher.
Motorists were told to follow the hollow triangle diversion symbol.
There was around 2.5 miles of queuing traffic on the approach.
