Detectives investigating the abduction of South Windsor resident Brendan Vollmost told the Gazette they are treating the case as a homicide.
Robbery and Serious Crime Detective Inspector Michael Banfield said although investigations are progressing well, there is no indication that he is alive.
"His bank account hasn't been touched since his disappearance and no-one has heard from him since," detective Banfield said.
"We still haven't been able to locate his body or the car even though we have had lots of people call Crime Stoppers with information."
The 24-year-old builder was last seen entering the yard of his home on Cox Street in South Windsor at 10.30pm on Tuesday, March 31.
Police believe Mr Vollmost was involved in a collision with a white Hyundai i30 just before his disappearance.
He fled to his home after the accident and was followed into his backyard shed by a group of men called the 'Blood Brothers'.
He was chased, assaulted and taken by four men from the property he shared with his girlfriend.
It is believed Mr Vollmost was carried, put into a white station wagon and was driven off.
Neither Mr Vollmost nor the Hyundai i30, with NSW registration BNY 72R, have been seen since.
Detective Banfield said no-one deserves this kind of treatment and it's unfair for the family to deal with the uncertainty.
He added it's the first time police have heard of the group 'Blood Brothers'.
"They aren't an affiliated gang, we just believe they are a group of boys who grew up together in the Western Sydney area. We think they might be from Blacktown all through to Windsor."
He said there had been a large number of people calling Crime Stoppers anonymously with information but refuse to identify themselves.
"If callers don't identify themselves, it makes the investigations harder because anyone can call and say they know they offenders. We need people to tell us how they know them through life experiences and be specific."
Police have released CCTV footage taken from the outside of Mr Vollmost's home in the hope someone will come forward with information.
Detectives are relying on people to identify anyone in the CCTV footage even though it's not clear.
"We hope that someone might recognise the people depicted by their clothing or mannerisms, or have information about the incident they can share."
Mr Vollmost's mother Tammy Slade won't give up until she has some closure.
"This is so not fair, I want to know where my son is," she said.
"How much longer can you people keep this a secret. He was your friend and as you all say, where is your loyalty. Help me get these boys, they can't get away with this."
A Facebook page, Please help bring Brendan home, has been set up by his girlfriend, Jennifer Carrier, calling for help to raise money to fund a reward for anyone who can supply information regarding his whereabouts.
Also known as Volley, Mr Vollmost was born and raised in the Hawkesbury.
He spent his primary school years at Hobartville Public School and went on to attend Richmond High School.
Do you know any more information? Email Rita Rizk on rita.rizk@fairfaxmedia.com.au
