THE A272 is closed in both directions following a "very serious incident".
Police have shut the main road at Hinton Ampner, near Cheriton, between West Meon and Winchester.
Drivers will need to avoid the route between Hinton Hill and Wood Lane.
An air ambulance has attended the scene and South Central Ambulance Service is assisting.
Hants Roads Police tweeted: "We have closed the A272 whilst we deal with a very serious incident.
"The incident that we are dealing with is taking up all these medical staff. We are still to establish the facts, but we ask you, is your journey essential?"
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