Australian police say bomb squad officers are working to dismantle a suspicious device strapped to a young woman.

Police declined to confirm reports that a “collar bomb” has been strapped to the 18-year-old woman, who called police to a house in an exclusive Sydney neighborhood Wednesday afternoon. But a spokesman confirmed to the London newspaper The Guardian that the young woman is unable to get away from the device.

Streets have been closed off around the house, in a neighborhood filled with multi-million dollar mansions. Some reports said the teenager's parents had received a ransom demand.

Police described the process of dismantling the device as “very delicate.”