Sydney: Sydney`s iconic Opera House was cordoned off on Thursday with ferries cancelled or delayed and people cleared from the harbour front amid a police operation.
Tourists were being kept about 150 metres (500 feet) away from the building, with half a dozen police officers and security personnel guarding the area, an AFP photographer said.
A small police boat was also seen patrolling along the front of the Opera House, which faces Sydney Harbour.
An Opera House spokeswoman would not make any comment.
NSW Police would also not comment, but told AFP there was also an ongoing operation at the coastal suburb of Manly on Sydney`s northern beaches.
A Manly to Circular Quay ferry was cancelled during to the operation, Transport NSW spokeswoman said.
In January last year, an unattended package left on a Sydney ferry sparked a lockdown of Australia`s harbourfront.
The package was later revealed to be training equipment used by the transport company running the ferries.