A lorry has shed its load on the A34 Queensway roundabout in Stafford.
Police say machinery weighing around 100 tonnes has come off the back of the vehicle, near the junction of the A518.
Drivers are being warned to avoid the area as one lane is blocked, causing heavy congestion.
A traffic light control box has also been damaged, which has resulted in the traffic lights failing on the island.
The road will be closed from around 10pm this evening (12 February) to allow for two cranes to recover the machinery.