National Highways Yorkshire said that there was “just over two and a half miles of congestion” on the approach. As of 8pm, three lanes of the southbound carriageway had been closed, but one was then reopened at 8.30pm.
The accident occurred between Junction 33 and 34, where the motorway sits between Sheffield and Rotherham.
National Highways said it does not expect normal traffic conditions to return until at least 10.15pm.
It described the reason for the closure as an “accident involving an overturned vehicle”, adding that several vehicles were involved.
It is as yet unknown how many vehicles were involved in the collision.
It added: “Our Traffic Officers remain on scene whilst recovery is ongoing for the vehicles involved in the collision.”
National Highways currently estimates that the incident will be cleared by 9.45pm.
Junction 33 is the intersection with the A630, while Junction 34 is the turn-off for the A6178.
More to follow…