Police have confirmed that one person has died following the collision on the A34 southbound this morning.
The southbound carriageway of the A34 and the A30 running parallel are both closed and will be until this evening.
The collision has totally blocked the southbound carriageway just out of Bullington and crossed over onto the A30, which runs parallel.
The southbound carriageway of the A34 is closed between the A303 and the A27.
The A30 is also closed in both directions.
Police are working with partners from Highways England to ensure we get the road open as soon as it is safe to do so.
Diversions are in place. For motorway traffic diversion are via the A30 and M3. For non-motorway traffic diversions are via the A33.
Officers were called at 9.19am on Tuesday following the collision involving a lorry, a van and a car on the southbound carriageway.
A spokesperson for Hampshire constabulary said :They could confirm that one person has died, two people have been taken to hospital with serious injuries and one person has been taken to hospital with minor injuries.
Investigations are ongoing into the exact circumstances of the collision and as a result of this and the need to ensure the road is safe before it is reopened, the carriageway is expected to remain closed until this evening.
We are working with our colleagues from Highways England to ensure we get the road open as soon as possible.
Officers would like to speak to any motorists who were driving in either direction of the A34 at around 9am this morning as they may have information that could help with the ongoing investigation.
Anyone with information is asked to contact us on 101, quoting incident number 238.