Police who are conducting a line search in Melbourne's outer south-east are believed to be looking for a body.
Police and SES search teams were combing an area of a busy highway in Frankston on Friday afternoon looking for buried remains.
They were searching under bushes, digging up dirt and even in drains.
Forensic police were also on scene and spray paint marks were made on the road.
However, police would not reveal more details of the investigation, except to say the search was part of an ongoing investigation. It is reportedly an historic, cold case, murder victim.
"We will not be commenting further," a spokesman said. "More information will be released at the appropriate time."
The victim's family have yet to be told about the development and there is no one in custody over the suspected murder.
Frankston Freeway was closed in both direction, with the northbound lane still closed between Moorooduc Hwy and Frankston-Dandenong Road.
Police are on site directing traffic.
VicRoads is advising motorists to avoid the area by seeking an alternative route.