The local community was "shocked and appalled" by the killing of Lee Irving, while his mother branded his murderers as bullies.
Six people were arrested over the killing of the East Denton man, who had learning difficulties.
The 24-year-old was described as "vulnerable" and his murder was called a disability hate crime by investigators.
Irving was found on a grassy area in the Fawdon area of Newcastle on 6 June. He was declared dead at the scene by emergency services. A murder inquiry was launched following a post-mortem examination but a cause of death has not been revealed.
Two women and four men have been arrested on suspicion of murder.
A statement from Irving's family said he was "loved by many".
"He will be very sadly missed by all who knew him," it said.
"What we have lost is irreplaceable and we must live with our loss every day.
"We would like to thank everyone who has supported us at this devastating time.
"Lee will always remain in our hearts and thoughts."
His mother Bev wrote on Facebook that her son was "killed by "a bunch of f** bully (sic) he had the mind of a eight year old xc ".
Superintendent Bruce Storey told the Chronicle: "It's thought those involved in this incident know each other.
"Lee had learning difficulties and was vulnerable.
"One of our key lines of inquiry was to establish whether this is a factor in his death and a motivation in this crime.
"It's important those suspected of being responsible face the consequences of their actions and I would urge anyone who was in Fawdon on Saturday morning, between 7am and 9am, to come forward and speak to us.
"If they saw anything at all that seemed out of the ordinary, no matter how insignificant they think it is we would ask them to get in contact.
"Extra officers will continue to carry out patrols in the area to offer reassurance to the local community, who understandably are shocked and appalled by this tragic death."