'Significant disruption' on A12
Part of the A12 has closed and police have warned drivers to expect "significant disruption".
Essex Police said both carriageways have been shut at junction 25 at Marks Tey near Colchester after officers were called to the scene at about 10:25 BST following "concerns for the welfare of a woman".
A woman has been left in the care of the ambulance service, police said.
"Thank you for your patience while we carry out this work with our emergency service partners and plan your journeys accordingly," a force spokesperson said.
Traffic has been diverted through the exit and entry slip roads at the junction.
National Highways also warned drivers of delays of at least 40-50 minutes.
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