A manhunt is underway for Jefferson Lewis, 47, alleged to have taken Sharon from Old Timers town camp near Alice Springs late on Saturday night just six days after he was released from prison.
Police on Wednesday said items found at a crime scene near the town camp including a shirt and a child's underwear were being forensically examined and the possibility of sexual assault was "on the table".
Northern Territory Police Commissioner Martin Dole said police were appealing for information from the community.
"We believe that there are members of the community that absolutely know where Jefferson Lewis is," he told reporters in Alice Springs.
The smallest detail from the public could be the one that unlocks the investigation, Mr Dole said.
Assistant Commissioner Peter Malley said police believed Sharon was still alive but the longer it took to find her reduced the chances of that.
"She may have come to harm but we still think she's alive and our number one mission is to find her safe and well."
Mr Malley warned anyone sheltering Lewis would face charges.
Scores of police officers, defence force members, Aboriginal trackers and volunteers have been scouring tough desert terrain to find Sharon and her alleged abductor.
Alice Springs Mayor Asta Hill told AAP a town council meeting on Tuesday night was opened with a prayer for Sharon and her safe return.
"There is intense worry reverberating through the whole community, it's as though the whole community is holding its breath," she said.
The community had united over the last few days with a single purpose - to bring Sharon home safely, the mayor said.
Lewis is believed to have lured Sharon away after he was seen holding a little girl's hand during a party at the camp.
Between 2016 and 2025, Lewis was sentenced to 64 months in prison for offences including aggravated assaults, breaching domestic violence orders, bail and resisting police.
NT Chief Minister Lia Finocchiaro issued a stern message to Mr Lewis to "hand her in, go to the authorities".
"It's very distressing, particularly for the family," she told 2GB on Wednesday, referring to Sharon as a "gorgeous little girl".
"I have just been looking at my phone waiting for a call from the police commissioner to tell me that they've found her."
No sightings have been confirmed but police did not rule out the pair being within an established 20 square kilometre search zone, telling media on Tuesday they believed the girl was still alive.
Sharon was last seen by her family when she was taken to bed about 11.30pm on Saturday, at the town camp of nine households and 40 residents.
She was reported missing about two hours later.
Police do not have a motive for the alleged abduction, but released more detail on what they believe happened before Sharon disappeared.
Sharon and her mother had been visiting a home at Old Timers to do some laundry, police said.
A social occasion was later held at the house where Lewis was staying.
Police were called out to the party but no offences were detected, and have since released images of Lewis captured that night.
Lewis was probably under the influence of alcohol and was seen "holding hands with a little girl" about 11pm, police said.
He allegedly led the girl towards an area that has been declared a crime scene - near Alice Springs Telegraph Station - and both have been missing ever since.
Police do not believe Lewis had access to a vehicle but did not rule out that someone could be driving him around.