More than four miles of traffic has built up due to a lane closure on the M62.
Highways England said they had closed lane 2 of an exit slip road due to a broken down van.
The incident has taken place at junction 29 (Lofthouse), on the eastbound exit slip from the M62 to the M1.
Traffic officers are on the scene.
Around four and a half miles of traffic has been reported on the eastbound carriageway as the incident is dealt with.
Update, 11:48am: Highways England tweeted: "UPDATE - #M62 J29 #Lofthouse eastbound exit slip to #M1. #TrafficOfficers have moved the broken down van to a place of safety. Lane two has been re-opened."