Police are investigating whether a motorist killed in a crash in Sydney's southwest may have been an innocent bystander in an illegal street race.
A witness has told police they saw the Honda convertible accelerate next to a motorbike on the Hume Highway at Warwick Farm shortly before eight o'clock last night.
Both were travelling side by side when the Honda driver lost control - crossing from the middle lane into the right-hand lane, then over the median strip and into oncoming traffic.
It crashed into a Toyota Hiace van - killing the 50-year-old driver instantly, a 17- year-old girl who was a passenger was injured.
Police are investigating whether the Honda and motorbike had been drag racing -- the bike sped off - it's been described as being red, black and white.
The Honda driver remains in a serious condition in hospital.