There are traffic queues building on the A14 following a crash involving two lorries.
Police officers are at the scene of the HGV crash.
The crash has blocked the eastbound carriageway of the A14 between junctions 27 (Conington) and 28 (Boxworth).
Congestion on the road is already building, with queues back to junction 26 and with drivers claiming tailbacks stretch four miles.
The incident was first reported at 12.52pm, and delays are expected to last more than two hours, according to Highways England.
Normal traffic conditions aren't expected to return until 3.45pm.
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