The A12 between Ipswich and Colchester has fully reopened after it had been closed by police following a collision.
The incident happened at Stratford St Mary shortly after 5pm, National Highways said on Twitter.
Traffic is now moving as usual and emergency services have left the scene, after police had closed off lane one of the northbound carriageway.
National Highways said the collision had caused more than five miles of congestion and added half an hour to motorists' journeys.
The conditions of the motorists involved in the collision are not known at this time.
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