National Highways is advising drivers that the M1 may remain closed southbound for some time between junction 42 (Lofthouse) and junction 41 (Wakefield / Morley) following a serious incident.
The carriageway is expected to be shut for several hours because a police-led investigation is still being carried out at the scene as well as the attendance of an air ambulance.
There was a collision involving two vehicles around 4.40pm this afternoon.
There are long delays approaching the closure with both the M1 southbound and the M621 clockwise carriageways becoming congested as a result.
Traffic travelling from further afield and heading south are advised to use the A1M.
If this closure impacts on your planned route, please allow extra journey time. Plan ahead, you may wish to re-route or even delay your journey.
Further information is available from Highways England by visiting our www.trafficengland.com website and travel apps, or via our regional twitter feed. Our 24/7 contact centre team is also available to provide up to the minute information on 0300 123 5000.