Major Collision Investigation Unit detectives have interviewed a man following a death in Kiata last week.
A passerby located human remains on the Western Highway just after 8am on 4 April.
The deceased is yet to be formally identified at this stage.
The cause of death is also yet to be determined but is being treated as a possible hit-run at this stage.
Detectives located a truck in Tullamarine today and have seized it for forensic testing.
A 33-year-old South Australian man, believed to be the driver, has been interviewed and released pending further enquiries.
Investigators are urging anyone with information or dashcam footage to please contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au.
