The man at the helm of the high-profile NSW police investigation into the disappearance of William Tyrrell says it's "unacceptable" the little boy's family is still waiting for answers two years on.
Detective Chief Inspector Gary Jubelin on Monday announced a $1 million reward, the largest offered in the state's history, for information leading to William's return, dead or alive.
The small mid-north coast town of Kendall mobilised in the days after the three-year-old disappeared on September 12, 2014, combing the dense bushland surrounding the property where he vanished, in a search that continued on and off for months.
DCI Jubelin acknowledged that in the first days and weeks after William disappeared, investigators focused on the possibility they were dealing with a "little boy lost".
But it was now clear that the boy in the Spiderman costume had not wandered off but had met with foul play as he played in his grandmother's yard.
"It's unacceptable that two years down the track we haven't found out what's happened to William," DCI Jubelin said.
"If he's alive, or if we find William's remains, as unpalatable as that sounds, we've said to the family we're going to do everything possible to find out what's happened to William."
He has also dismissed as "vindictive" any lingering suggestions that William's own relatives were involved in his abduction.
"I've personally interviewed the family and I'm saying they've had nothing to do with it," DCI Jubelin said.
He could not rule out the possibility that a paedophile ring was involved in snatching the little boy but would not discuss any of the 690 persons of interest identified so far as part of the broader investigation.
He has also urged members of the public not to waste detectives' time with tip-offs about "clairvoyants or dreams" and spurious sightings.
"If a child's getting round in the McDonald's carpark in a Spiderman suit now, two years after William's disappeared, we're not particularly interested," he said.
"But what we would be interested in (would be) if anyone's got concerns about the circumstances in which a child has come into a family."
