A woman has died and four other people, three of whom are children, were seriously injured after a crash on the Wendover bypass on Friday afternoon.
The three vehicle accident happened on the A413 Wendover bypass near to the railway station at about 4.45pm on June 7.
A Land Rover Discovery, a Ford Focus and a VW Golf were all involved in the collision.
The Ford Focus and the VW Golf were travelling towards Great Missenden and the Land Rover was travelling towards Aylesbury.
The woman who died was driving the Ford Focus and she was pronounced dead at the scene.
Three passengers from the Ford Focus, all children, were taken to the John Radcliffe hospital in Oxford with serious injuries - one of them has since been discharged.
The driver of the Land Rover Discovery was also taken to the John Radcliffe Hospital with serious injuries and he remains in hospital.
The driver and passenger in the VW Golf were uninjured.
Investigating officer PC Lyndsey Blackaby said: “Sadly a woman lost her life in this collision and three young children and a man have been seriously injured
“We would ask anyone who was travelling in the area of the Wendover bypass, or believes they may have information or a dash-cam recording relevant to our investigation, to make contact with police.
“If you have any information call 101 or visit our website https://www.thamesvalley.police.uk/tua/tell-us-about/cor/tell-us-about-existing-case-report quoting reference 43190171919.
“We would like to thank motorists and local residents for their cooperation and patience while the road was closed for five and a half hours so officers could carry out forensic examinations.”