BILL Pulver says his family will not feel safe until the man who strapped a hoax bomb around his daughter's neck is caught.

"There is a residual fear that exists in all of us. He is still out there," Maddie Pulver's dad said.

He dismissed suggestions his daughter's 10-hour ordeal with a collar bomb around her neck was an elaborate prank gone wrong.

"The Assistant Commissioner of Police (Mark Murdoch) described it as an elaborate and complex device. So to answer your question, no. I don't think this is a prank," he said.

"Clearly I'm no expert, I'm a complete rookie when it comes to all of this, but you've got the best and the brightest in the police force working on this, and they have given me no indication of that."

The family returned to their Mosman house on Thursday, the night after the traumatic saga.

Mr Pulver yesterday revealed details of what occurred in the luxury house while Maddie was alone with police bomb experts and negotiators. She had to sip water through a straw and was so traumatised she could not eat.

Police gave her a chocolate bar, but she was too distressed to eat it.

"So the chocolate bar remained there beside her," Mr Pulver said.

To help him and his family cope with the media glare, he has hired a public relations adviser.

NSW Police Commissioner Andrew Scipione said the crime had created shockwaves around the world.

"It is a serious matter," he said. "This is the sort of crime we haven't seen in Australia before. For that reason, it's important we keep a close watch on it.

"This has gone viral literally around the world, we understand that."

'The bravest girl in the world'

Earlier yesterday, a brave Maddie stepped out for the first time since the trauma.

Holding her mother Belinda's hand, Maddie smiled politely to the photographers outside her home as she climbed into the back seat of the family car between her two brothers. The boys were dropped at Shore School, while Maddie stayed with her parents.

Asked how she was feeling, Maddie said: "I'm OK, thank you."

Police said they had spent hours with Maddie trying to identify her attacker.

Detectives questioned her about what she remembered before and after the authentic-looking device was strapped to her neck.

"The sound of his voice, distinctive smell, height ... anything nuance-like that will help investigators," a senior police source said.

Forensic evidence gathered at the scene is already at a Sydney laboratory and analysis of DNA or any other trace evidence gathered from the home is being treated urgently.

"The investigation and forensics are being given priority," a senior officer said.

"Obviously every detail or piece of information Maddie gives is vital and is being investigated thoroughly."

Police were keeping an open mind on any possible motives.

"It is very early in the investigating and all possibilities are being canvassed," he said.

Police were looking at Maddie's social circle and her father's business.

Mr Scipione said it was likely to be a long in- vestigation, but was well advanced.

Police said a note made no demand for money but warned attempts to call police or defuse it would result in detonation.

Yesterday Constable Karen Lowden from Harbourside Local Area Command spoke of the time she spent with Maddie during her terrifying ordeal.

Constable Lowden told of how distressed Maddie was when she arrived but how well the girl coped.

"She was quite distressed but she held herself so well and was composed. She knew what she had to do to get through that situation. I didn't feel like a heroine. You have to deal with the unexpected in this job. You knew there was a girl that needed help.

"I had to reassure Maddie I was there for her and I told her she was very brave. I said it was a different situation for both of us and we needed to get through that process.

"Having a child myself I knew I wanted to be there for her.

"It didn't feel like a different job and I had the full support of my colleagues who were amazing. I never felt like I was alone.

"She is the bravest girl in the world."

Constable Lowden spoke about her role in the drama outside North Sydney Police Station.

Constable Lowden was one of the first officers on scene where Madeleine had a suspicious device attached to her neck.

She stayed with Maddie and provided emotional support during the early hours of her ordeal.

Police say they are well on track in their to find Sydney schoolgirl Madeleine Pulver's hoax collar bomber after her 10-hour ordeal on Wednesday.

Police said this morning the crime had gone "viral" around the world but they would not provide a running commentary in case it jeopardised the investigation.

Although they say they are "well advanced" in their investigations they say the unique nature of the case will mean it will be "some time" before it is concluded.

Neighbour saw suspect

The driver of racehorse trainer Gai Waterhouse said Mrs Waterhouse, who lives in the same street as the Pulvers, spoke informally to officers after she and her driver saw a woman "driving up and down the street, looking nervous".

The driver then saw a man run from the vicinity of the Pulver house and jump into the car before the two fled at "significant speed".

Mrs Waterhouse was inside her house preparing for the David Jones spring fashion launch when the man made his escape.

"Some crazy person had supposedly tied a bomb to young girl who lives down the street. What is our world coming to, if people can't feel safe in their own homes," Mrs Waterhouse wrote on her blog.

"This young lady could easily be affected for life by this horrendous experience. How dare someone violate the privacy that she and her family are entitled to, not to mention the unimaginable terror and strain they were put under, the boot should be put on the other foot."

Note connection

It has also emerged Police found a handwritten, two-page note attached to the device included the name Dirk Struan, the lead character in the epic historical novel Tai-Pan, by James Clavell.

The 1966 novel tracks the bitter feud between rival businessmen who seek to destroy each other. Eerily, one passage in the book refers to an extortion threat to Struan. In chapter 12, Struan learns there is a price on the heads of his mistress and children - one that is doubled if they're kidnapped alive.

A character named Mary Sinclair tells him: "That's not all, Tai-Pan. You should know that the reward on your head is doubled and on May-may, Duncan and Kate. If kidnapped alive."

Also in the letter were a series of instructions directing Maddie to make contact with the extortionist via the internet. There were no demands for money.

Police said the letter, described as coherent but amateurish, is now the most crucial piece of evidence investigators have to help them to track down who broke into the family home.

Looking for clues

Yesterday a specialist strike force from the Robbery and Serious Crime Squad spent the day studying the wording of the note for any clues that could help them catch those responsible for the attack. The note said: "Don't go to the cops or I will detonate. Don't cut the wires or I will detonate."

At the palatial Burrawong Ave house yesterday, forensic experts meticulously checked every room, fingerprinting walls and doors, even moving furniture to inspect behind it.

Outside the harbourside home, Riot Squad officers scoured the garden and nearby yards looking for clues, at one stage even closely studying a tree trunk and looking at its markings.

Laptops seized

But it was in the study of the Pulver residence where detectives appeared to spend a significant amount of time, focusing on a computer.

Sources said police later seized several PCs and laptops from within the home in an attempt to see what websites had recently been accessed, or if anyone was shadowing Maddie via the internet.

"It is something we are quite interested in - that's not unusual in an investigation of this type," a senior police officer said.

An exhausted but unharmed Maddie spent a few hours in Royal North Shore Hospital being checked after she was released from the bomb hoax early yesterday, before going with her family to a city hotel, where they spent the day.

She was visited by a small group of her closest friends.

Robbery and Serious Crime Squad head Superintendent Luke Moore said police were treating the incident as a "serious and complex investigation" and an unusual crime.

Although it has been revealed there was no demand for money in the note attached to Maddie's chest, Supt Moore said police were treating it just as seriously and had thrown specialist resources into taskforce Strike Force Haddon."We are treating this as an attempted extortion," Supt Moore said.

He was quick to dismiss suggestions that Maddie was a person of interest in the hoax, saying: "Madeleine was the victim."

- With news.com.au and AAP