SYDNEY: A police operation that evacuated the Sydney Opera House was sparked by “information on social media,” sources said.

Police ran operations at the Opera House and in the beachside suburb of Manly on Thursday, but did not provide details on the nature of the threat.

Helicopter shots showed the usually crowded hub completely deserted and afternoon concerts were canceled.

Police issued a release at 15:30 (local time) saying that both operations had concluded.

The operation resulted in the cancelation of one ferry service between Manly and Circular Quay.

“Following information on social media, police conducted an operation in the vicinity of the Opera House and Manly as a precautionary measure,” NSW police said.

The 1.20 p.m. ferry from Manly to Circular Quay was canceled due to the operation.

The usually bustling Opera House tourist hub was left eerily quiet, and temporary fences were erected to keep people back.

A Sydney Opera House tour guide said she had been leading tourists around the building when police arrived.

“My tour was stopped mid tour... now I can’t get back in,” she told AAP.