Broken traffic lights caused traffic disruption on the A47 in King's Lynn earlier this afternoon.
Lengthy delays were caused close to the Hardwick Roundabout in the town after the traffic lights went out.
In a tweet, Norfolk police urged drivers to find alternative routes.
There was also slow traffic on the A148 Gaywood Road in both directions between the A149 Hardwick Road and the B1144 Tennyson Avenue.
Queues were also formed on the A148 Lynn Road from Norfolk Street to the A1076 Gayton Road at the Clocktower traffic lights.
Elsewhere in Norfolk, there were six minute delays on the B1108 Norwich Road in Kimberley, with an average speed of 15 mph.
As of 6.10pm, the traffic lights had been fixed and were working correctly.
For up-to-date information about the county's roads, visit our LIVE Norfolk traffic map.
Join our Norfolk Travel Information group on Facebook for all the latest traffic news in Norfolk.
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