The cab of the truck landed right-way-up in a nearby paddock. Photo / Dean Purcell A neighbour who ran from his house to assist was alerted to the crash by a "huge thud."
"I went and helped control traffic because there was metal and bits of truck all over the road."
The man, who did not want to be named, said the driver of the rolled truck and his female passenger were badly injured.
"They were pretty bad, they were in the truck and trailer that had rolled and it was the right way up in the paddock."
Other motorists gave assistance to the injured until emergency services arrived.
The man said both trucks were carrying metal. It is understood one was from Brookby Quarries Ltd and the overturned truck was from Whitford Quarry.
A spokesperson for the fire service said it had four trucks on the scene assisting ambulance officers. Police were also in attendance.
The area is understood to be a high crash site. Photo / Dean Purcell Brookby Rd is closed between Twilight Road and West Road and diversions are in place.
The Commercial Vehicle Investigation Unit (CVIU) has been notified and will be investigating.
The area is understood to be a high crash site.
Local resident Leanne Chamberlin said there had been at least five crashes on Brookby, Alfriston and Whitford Park Roads in the past 18 months.
"It is a combination of narrow roads that were not designed for 2000 trucks a day and visibility issues," Chamberlin said.
"Residents are constantly relating instances of dangerous driving."
A traffic report presented to council last year recorded 58 crashes on Brookby, Whitford and surrounding roads over a five year period from 2008 - 2012.