A woman and her unborn baby have been killed in a head-on crash in Melbourne's southeast, with police now seeking dash-cam footage of the incident.
A utility collided with an SUV in Pakenham South on Thursday morning, with the female SUV driver airlifted to hospital in a critical condition.
The 34-year-old from Koo Wee Rup and her unborn child had since died, police confirmed on Friday.
Two young children were also in the vehicle at the time of the crash and suffered non-life-threatening injuries.
Investigators have been told the ute hit several other vehicles before the collision, causing minor damage.
Its driver remains in a critical condition in hospital as police investigate the circumstances of the deadly crash.
Anyone who witnessed the accident or has dash-cam footage is asked to contact police.