A section of the M1 between J20 and J1 of the M1 has been closed after a serious police incident.
The northbound carriageway between the two junctions in Leicestershire is not expected to re-open until after the morning rush hour.
Traffic is reported to be leaving the motorway at J20 as a diversion was put in place to move motorists away from the closure.
Delays are building up on the approach to the closure.
The police incident happened around 3:45am this morning.