FOUR people are being treated following a serious crash on a busy Hampshire road.

Police said the accident occurred at around 3.30pm on the A34 southbound, near the Whitchurch junction.

The road is closed in both directions as Thames Valley & Chiltern Air Ambulance, three ambulances, a basics doctor, and the hazardous area response team attend to the casualties.

It is believed two vehicles were involved.

The road is expected to remain closed for some considerable time.

Southbound traffic is being taken off at the junction with the A343.

Northbound traffic is coming off at the Bullington Cross junction.

Traffic on the A34 northbound is already stuck in queues and being diverted onto the old A34 at Burghclere.

A spokesperson for Hampshire Constabulary said: “Officers are asking for people's patience and understanding whilst they work with our emergency service partners on a very serious incident.”