A carriageway of the A14 near Ipswich is currently closed after a vehicle crashed into the central reservation.
Officers are currently at the scene of the single-vehicle crash in the westbound carriageway near the Seven Hills Interchange.
In a Tweet, Suffolk police said: "There is heavy traffic on the A14 westbound near Ipswich following a single-vehicle collision between the Seven Hills roundabout and the Orwell Bridge.
"This is also causing congestion on the A12 southbound.
"The road is currently closed westbound."
A spokesman for Suffolk police said that no injuries have been reported as a result of the crash.
According to the AA Traffic Map, there are severe delays in the area on both the A14 and the A12 while emergency services attend the crash.
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