The Cold Case and Missing Persons Squad has taken over the investigation into the disappearance of Jake Lyons after information recently provided to local detectives raised their suspicions.

Mr Lyons, 20, was last seen when he left his Dandenong North home on August 25 and has not made contact with friends or family, used social media, or accessed his bank account.

His car, a 2006 Holden Astra sedan, was found at Warner Reserve in Springvale, about seven kilometres from home, six days after his disappearance.

Police were searching the reserve on Tuesday for any sign of Mr Lyons.

Mr Lyons' father, Rick, told local media in November that his son was depressed and had been receiving counselling before he disappeared.

Rick Lyons said that in late August he had returned home from work between 5pm and 6pm and found the house unlocked, the stove gas turned on, and his son gone. Mr Lyons had dismantled his phone and computer before leaving the house.

Detective Inspector Jill Dyson said it was possible Jake Lyons had met someone in the park, but there was nothing abut his lifestyle that indicated he could have been murdered.

She would not reveal details about the information that had resulted in her squad taking over the investigation, but said there had also been other information discovered since, which suggested the disappearance was suspicious.

"It's probably too early to say whether there's any people of interest," Detective Inspector Dyson said.

"There's certainly information we're pursuing. We haven't actually followed that to the end of the inquiry and hopefully when we do we'll be in a position to discuss it further."

Police are conducting line searches with State Emergency Service volunteers in the busy park, which includes a cricket oval and a concrete culvert along its southern edge. Police divers may also scour a nearby lake after the search on Tuesday.

The park had been searched by local police after the car was discovered, but not in as much detail.

Jake Lyons is about 178 centimetres tall with a medium build, straight brown hair, and unshaven, and was last seen wearing green jeans, a blue jumper and black runners.

His car was again seized by police from his Scullin Street home, where he lived with his father, last week.

Rick Lyons said in the Dandenong Leader in November that not knowing what had happened to his son was tearing him apart.

"Jake, if you're out there, mate, I'd like you to ring me to let us know that you're OK," he said.

"We love you and we miss you, we're worried sick about you."

Anyone with information is asked to contact Crime Stoppers on 1800 333 000.