A two-vehicle crash on the A11 caused heavy delays.
Road users reported being at a standstill on the Attleborough Bypass close to the town on Sunday morning (January 9) after 9.30am.
Following the incident, police urged drivers to avoid the area and find alternative routes.
A Norfolk police spokesman confirmed that there was not "believed to be any serious injuries" but that an "abnormal load" was waiting to be moved before traffic could pass.
He said: "There's an oil spillage in the road so we're waiting for recovery to arrive before the road can be reopened."
Police, fire and ambulance all attended the scene.
The disruption could affect travelling Norwich City fans on their way to London to watch the FA Cup match against Charlton Athletic.
For up-to-date information about the county's roads, visit our LIVE Norfolk traffic map.
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