The A27 is open again in both directions between A259 Havant Road and Fishbourne Roundabout and disruption has cleared.
Sussex Police have confirmed that a 25-year-old man from Havant died in the crash at 11.40pm.
A 19-year-old also suffered life-threatening injuries and has been taken to hospital for treatment.
Motorists were earlier warned that there was heavy traffic on diversions routes this morning as a result of the closure.
The A27 was shut for a number of hours.
A spokesman for Sussex Police said: ‘The road is likely to be closed in both directions between Fishbourne and Emsworth roundabouts for some time whilst the investigation takes place, and motorists are advised to seek alternative routes.’
Police are appealing for witnesses and are interested to hear from anyone with dash cam footage of the collision or the Golf being driven prior to the incident.
Follow all the latest traffic updates in our blog below.
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Traffic updates as A27 remains closed after fatal crash
Last updated: Thursday, 11 February, 2021, 17:07
A27 has now reopened
Tributes paid to Havant man as police search for driver of Audi car
Tributes have poured in for a Havant man who died in a crash.
The Mayor of Havant, Councillor Prad Bains, told The News: ‘It’s so sad when things like this happen, especially to somebody so young. My thoughts are with the families and friends.'
A27 remains closed
What have police said?
A spokesman from Sussex Police said: ‘At 11.40pm on Wednesday, February 10, a black Volkswagen Golf was travelling east towards Chichester on the A27 when it crashed.
‘The driver was sadly pronounced dead at scene. The passenger – a 19-year-old man from Havant – suffered life-threatening injuries and has been taken to hospital for treatment.
‘The road is likely to be closed in both directions between Fishbourne and Emsworth roundabouts for some time whilst the investigation takes place, and motorists are advised to seek alternative routes.’
Traffic map shows delays across the area following A27 closure
Long delays on diversion routes this morning
A 25-year-old man from Havant has died
The crash happened at 11.40pm last night on the A27.
A 25-year-old man from Havant has died, while a 19-year-old man also from Havant, is in hospital with life-threatening injuries.
Welcome to our live blog
We will bring you all the latest updates throughout this morning.