Police have closed parts of the A149 after two separate crashes.
Both happened late on Sunday morning.
Norfolk Police said they were on the scene at Heacham where the King's Lynn-bound carriageway was closed.
"Please avoid the area and find an alternative route," officers said on Twitter.
Further east, the A149 is also closed at Antingham, between North Walsham and Cromer.
The AA's live traffic map shows the road to be closed in both directions for a shorts stretch from the Gunton Arms pub to Southrepps Road.
Traffic is being diverted through the village.
One person on social media said: "Main road traffic has been coming through Antingham for about an hour now."
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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