Police are investigating a teenage girl’s death days after she was found unresponsive at a home on Sydney’s Northern Beaches.

Emergency services were called to the home in Elanora Heights about 5.45pm on Sunday following reports of a concern for welfare.

The 16-year-old girl was found unresponsive and treated at the scene before being flown to Royal North Shore Hospital in a critical condition.

She remained in hospital before dying on Tuesday night.

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Police have now launched an investigation into the circumstances surrounding her death.

Officers attached to Northern Beaches Police Area Command are investigating.