Girl in Mosman bomb nightmare released

After close to ten hours, police have secured the safe release of a teenage girl who had an "elaborate device" attached to her body in an exclusive Sydney suburb.

The girl, identified as Madeleine Pulver from Mosman, was caught up in the terrifying ordeal after an intruder entered her family's multi-million dollar mansion and attached a suspected bomb to her.

The device is still intact and will be the subject of an investigation.

Reports suggest a balaclava-wearing man broke into the home of one of the richest families in Sydney, and fastened an explosive device to the 18-year-old's neck, with a threatening note attached.

She appears to be the only witness, and interacted with the person during the initial event. She called the police after the intruder fled the scene.

Ms Pulver is the daughter of a wealthy businessman, Bill Pulver, who is believed to be the target of the apparent extortion bid.

Earlier, Acting Deputy Commissioner Mark Murdoch told the media he could not confirm various media reports about the circumstances surrounding the incident, due to the "serious, sensitive" nature of the situation.

"I can't confirm whether it is strapped to the woman involved but she is still in the vicinity of the device," he said at the time.

When asked whether the girl could move away from the bomb, Mr Murdoch said: "No, she can't get away from it."

"This is a serious incident where the life of a young woman is potentially endangered," he said.

"We need to play our cards pretty close to our chest at this point."

Police and emergency services rushed to the exclusive Sydney suburb of Mosman at about 2.30pm on Wednesday, after being called to the home by the schoolgirl claiming there was a "suspicious device".

Nine hours on, she had still not emerged from the residence where emergency services were waiting on alert. She remained in a room to the front of the house, and was considered in a "very good" state for the situation.

"The young lady is fine and doing her best to assist the police to find out exactly what's gone on," Mr Murdoch said.

Police said the teenager had no direct contact with her parents, as they waited outside as the events unfolded at their home, communicating with their daughter through police. They were reportedly not allowed inside due to the threat of an explosion, but there were unconfirmed reports her father had entered the home.

Bomb disposal experts and negotiators worked with the girl throughout the day and night to secure her release.

The Robbery and Serious Crime Squad were called in to assist, leading to speculation the teenager had been caught up in an extortion attempt.

Mr Murdoch stated the police were speaking to a number of agencies and making inquiries internationally to assist in resolving the incident. He was clear they had not spoken to the person who left the device.

Initial radio reports claimed the woman was wired to the device and threatening to detonate it, with details of the possible extortion attempt becoming clear after police statements were released.

The house is in an area well known for its multi-million dollar properties, including one belonging to horse trainer Gai Waterhouse.

A middle-aged man and a woman were seen with police officers outside the house, with the woman wiping tears from her eyes, as a group of teenage girls gathered outside the police cordon.

Streets surrounding Burrawong Ave were roped off, as ambulance and rescue services arrived.

Some homes had to be evacuated and police are urging people to stay away from the area.

NSW Police released a statement just after 7pm AEST saying bomb squad officers remained inside the house where they were examining the device and supporting the woman.

"The process demands a high-level of skill and must be meticulous," the statement said.

"The incident is not being treated as self-harm."

Police would not elaborate on these details, due to the "delicate operation" which was in progress.

If you witnessed any suspicious behaviour in the Mosman area on Wednesday afternoon, please contact Crime Stoppers on 1800 333 000