Drivers face long delays on the M1 northbound this morning after a crash in Leicestershire closed the carriageway.
The collision took place between Junction 20 and Junction 21, according to National Highways.
The incident, which is described as serious, has impacted traffic in and around the Lutterworth to Leicester stretch of the motorway.
Emergency services are at the scene responding, with the carriageway closed in both lanes northbound. An air ambulance has been called to the scene.
New UpdatesView PostToday11:13 BST
National Highways has issued a diversion route for motorists affected by the M1 closure. Drivers are being advised to follow the Hollow Square diversion symbol on road signs while the carriageway remains shut between Junction 20 and Junction 21.
The diversion takes traffic off the M1 northbound at Junction 20 onto the A4303 westbound, passing through several roundabouts before reaching the A5/A4303 Cross in Hand roundabout.
From there, drivers are directed north along the A5 Watling Street for around 6.4 miles to the A5/M69 Junction 1 interchange, before joining the M69 northbound for approximately 9 miles and rejoining the M1 northbound at Junction 21.
National Highways has warned that the diversion adds significant extra time to journeys and has urged anyone affected to consider re-routing or delaying travel where possible.
Joe SmithToday11:13 BST
National Highways has said the crash happened shortly after 8am, with all emergency services attending the scene, including the Air Ambulance, alongside National Highways Traffic Officers who are assisting with traffic management, Leicestershire Live reports.
The agency has also confirmed that all traffic caught within the closure has now been released.
The closure between Junction 20 (Lutterworth) and Junction 21 (Leicester) remains in place while emergency services continue to deal with the scene, and National Highways has urged drivers to plan ahead and allow extra journey time.
Joe SmithToday11:10 BST
National Highways reported queueing traffic in the area, with delays of around 20 minutes currently building.
Motorists have been urged to allow extra time for their journeys, with the road not expected to fully clear until between 12.30pm and 12.45pm.
National Highways confirmed traffic was held shortly before 9.30am to allow the closure to be put in place, with emergency services remaining on scene.
No further details have yet been given about the exact nature of the crash, how many vehicles were involved, or whether anyone was injured.