An investigation is under way to determine whether a vehicle found during the search for the remains of schoolgirl Melissa Trussell is linked to her suspected murder 25 years ago.

The vehicle was uncovered on Garden Island today as divers searched through water and mangroves as a part of a fresh probe into her disappearance.

She was 15 at the time of her disappearance and her mother was 33.

Rosemary’s body was found in mangroves at Garden Island in Adelaide’s north-west on Sunday, July 2 in 2000.

However, her daughter was never located and police suspect she was murdered.

The search on the northern side of Garden Island for the remains of Melissa has been suspended for day, with police saying it will be continued another day.

A section of the vehicle’s front grill was taken from the scene to help police identify the vehicle.

Police are working to determine whether the vehicle is connected with the murder and suspected murder of the mother and daughter.

Depending on the results of the investigation, police recover the car for further examination.

Earlier today, South Australia Police detective superintendent Darren Fielke said police were “hopeful” they could find Melissa’s remains.

“This search demonstrates that we will not give up looking for answers,” Fielke said.

“We will continue to investigate this matter and will not stop until we can provide closure and hopefully justice for the loved ones of both Rosemary Brown and Melissa Trussell.”

Earlier this month, the family of Melissa issued a public plea for information 25 years after Rosemary’s body was discovered.

Melissa’s sister Kayla said the family had experienced “decades of pain” and just wanted answers.

“It’s all that we can really ask for,” she said.

“She was my best friend, we were just so close.”