A car has overturned on the A47 near Norwich this morning.
An Audi A5 and a Honda Civic crashed near the Thickthorn Roundabout shortly before 7.55am.
Norfolk police said the incident occurred off the slip road from the roundabout onto the A47.
The A47's southbound carriageway was only partially blocked during rush hour, but caused significant delays to traffic.
Police confirmed the road was cleared at 10.30am.
The BBC Norfolk Travel Twitter account said traffic was at a standstill at about 9am, with delays of up to an hour.
In a Tweet, it said: 'There's a collision on the Yarmouth bound side of the A47 at the A11 Thickthorn Junct. Things at a standstill on the approach, sensors saying at least an extra hour from Longwater. An extra half hour B1172 from Wymondham. An extra 40 mins A11 to St. Stephens Rbt.'
Bus operator Konectbus said there was a risk delays to its 6, X6, 8 and 501 service.
A police spokesman said it did not appear as though anyone had been injured in the crash.
• Updates to follow
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