Traffic was stopped on the M61 near Bolton following a serious accident.
Police officers and paramedics rushed to the accident scene near junction 8 and junction 6 on the southbound carriageway.
In a tweet, a Highways England spokesman warned drivers to move away from the highway and said all lanes were closed.
They said: “M61 traffic heading south from J8 (Chorley, A674, A6) to J6 (BoltonNorth.Horwich, A6027) has been temporarily blocked due to a serious collision.
“Traffic agents, the Lancashire traffic police, the GMP Traffic Unit, the Northwest Highway Police and the Northwest Ambulance Service are currently on the scene.”
The accident was first reported around 13.15 and is causing long delays for drivers.
Follow the real-time updates on the accident here …