Detective Inspector David Harbison said Gray’s NDIS carer and his relatives had provided information that proved “absolutely pivotal to the investigation”.
Four men were subsequently found and questioned, and a vehicle seized. Two of the men were released without charge, but are assisting police.
“Police allege Jai was stabbed multiple times by the two offenders that have been arrested for murder,” Harbison said.
“This is a callous, brutal, unprovoked attack on a young person that posed no threat to anyone.
“This is a callous, brutal, unprovoked attack on a young person that posed no threat to anyone.”
Detective Inspector David Harbison
“Police and Jai’s relatives are struggling to comprehend the unjustified actions of those persons responsible.”
Harbison said Gray was travelling in a car with the four men on the day he was killed, unaware of the danger ahead.
“There’s no suggestion Jai knew what was going to happen to him,” Harbison said.
Jai Gray’s remains were found at an abandoned quarry in the Glass House Mountains.
“We believe it’s a premeditated attack and he was taken out there deliberately to this isolated area to attack him ...
“We just understand it was over some very minimal debt ...
“It’s a senseless act and reverberates through our tight-knit community.”
Harbison said the two accused killers had lived with Gray at his Morayfield home.
“They had been living in an informal arrangement with Jai for some time. You wouldn’t call them housemates … It’s Jai’s house and these other two were probably taking advantage of that and living on and off in that location at times,” Harbison said.
The two Caboolture men are due to appear in court, charged with murder and interfering with a corpse.
Two of Gray’s grieving relatives addressed the media on Wednesday morning, describing him as a “very loved” member of their family and the Caboolture community.
“Jai has always been a very vulnerable person and [was] always generous and loving,” they said.
“Our family is so saddened by this tragic event ...
“We’re glad that our family asked questions and pushed to find Jai.”
Gray’s family also posted on Instagram with a statement asking for privacy.
“We want to extend our heartfelt thanks to everyone who shared, helped search, and supported our family over the past 14 days during Jai/Malahki’s disappearance,” they said.
“It is with deep sadness that we inform you there is no longer a need to continue looking for Jai.
“Please, take this moment to tell your loved ones how much they mean to you. Hug them a little tighter, listen a little longer, be present, say ‘I love you,’ take countless pictures together, and cherish every second.”