Some members of Israel's family had a lengthy meeting with police this week to present new information which had been shared with them since the case was put back in the public spotlight.
Police say there are "bits and pieces that are new and different" which warrant further investigation.
Detective Sergeant Tony Colby is warning those sitting on information to break their silence now and clear their conscience.
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"All cases can be solved. There are people out there who hold the key to that.
"Five years has now lapsed. There will be more people talking about it now because people talk.
"If they know something, I urge them to clear their conscience. The family is still hurting. It is still real and raw for them and we want to resolve it on their behalf."
Colby couldn't divulge details about the new information for operational reasons but said they would be making further inquiries.
Based on that, it would then be determined whether those inquiries warranted a full review of the case but Colby said they weren't at that phase yet.
"There is some work we need to do first."
Israel's father, Rendall Jack, was among those who had a meeting with police this week. He said he was pleased the new information had given police a reason to "open the file" on his son with a view to solving the case and bringing Israel's attackers to justice.
Rendall Jack believed his 20-year-old son was set upon unprovoked by gang members and associates unknown to Israel, possibly for a patch, as he walked along Te Ngae Rd in the early hours of August 18, 2013 on his way home after a night out with friends.
His body was found lying on Te Ngae Rd, between Pohutukawa Dr and Robinson Ave, at 4.25am after it had been run over by two vehicles not linked to his killing.
Police have said there was foul play in the minutes before those vehicles came along because less than five minutes earlier, at 4.20am, he was seen on security camera footage leaving Caltex Te Ngae, 1.4km from where his body was found. Police said Israel could not have walked that distance in that time.
Rendall Jack said the meeting this week had given him assurances the new information from different sources would be followed up.
"The very fact that the public are now more aware of the sinister nature of an intentional gang attack on my son, my greatest hope is that people who do know anything relating to his tragic death will clear their conscience and contact the police.
"It's either that or standing in the dock suffering the consequences of doing nothing."
Rendall Jack said there was only "one degree of separation" for many in Rotorua.
"To all the people who knew Izzy, his whānau or any of his family and friends, to all those also of Israel's Te Arawa descent, to anyone that cannot bear the thought of the same thing happening to someone they dearly love, you may in some way be in a position to help us stop the consequence of having to cope with our continual grief and being left in limbo.
"The secrets and silence hurt us the most, knowing his killers are walking the streets."
He said the situation with the case reminded him of a famous quote from Edmund Burke: "The only thing necessary for the triumph of evil is for good men [and women] to do nothing."
Rendall Jack said secrets surfaced, no matter how long it took.
"Five years is far too long yet we are not giving up."
The Rotorua Daily Post published an article about Israel's case three weeks ago as part of a wider look at the region's cold cases.
In it, family members said for the first time they believed gang members and associates were responsible and, also for the first time, police confirmed that was "probably" the case.
Three days later, a $10,000 reward was offered by an anonymous member of the public.
The man, who the Rotorua Daily Post agreed not to name, made the offer saying it was time Israel's killers were brought to justice. He said people knew the names, but didn't have the evidence.
He said he would set the money up in a trust account held with a lawyer and the money would be paid to a witness or witnesses after a murder conviction, and after all appeal processes had been exhausted.
Know something? Say something.
Any information can be given to Rotorua police on (07) 348 0099 or the anonymous Crimestoppers line on 0800 555 111.