Officers from Hampshire Constabulary have been working through the night to piece together the moments of how fatal collision took place.
Emergency services were called late on Monday night to the westbound carriage of the busy M27 motorway near Fareham after a car and a motorcycle were involved in a collision.
Moments before the collision many drivers made frantic 999 calls to police warning that large lumps of wood were in the carriage and many drivers were having to swerve to avoid them on the unlit section of the M27 between Junction 9 and Junction 8.
The section of motorway was closed for nearly eight hours overnight whilst specialists officers and collision investigators carried out tests, took measurements and scans of the collision site.
It understood that at least four vehicles were involved in the collision including a motorcycle and a Hyundai.
Shortly after 5.10am on Tuesday morning Police said they had completed their investigations at the scene of the M27 and handed over the reopening to Highways England.
Police are expected to issue an appeal and a further statement later today.
Anyone with information is that can assist officers they are asked to contact Hampshire Police on 101 quoting refer 818/20May