Sydney Opera House evacuated after reports of a suspicious package

Sydney Opera House was in lock-down today as authorities put in place a cluster of security measures across the city as the cafe hostage drama continued.

Staff have been allowed back into the Opera House, Sky News reports, but public are still required to stay clear of the area.

"Couldn't get near the Opera House without a bag search. Place is really quiet. Chopper still circulating," tweeted Mark Serrels 

 Reports of a suspicious package at the scene were unconfirmed.

Chopper at evacuated Opera House.

— Advocacy4Oromia (@Advocacy4Oromia) December 15, 2014

Police chopper hovers over a deserted Opera House concourse. #sydneysiege @cberkman

— ABC News (@abcnews) December 15, 2014

The Opera House evacuation came as up to 50 hostages are being held in the Lindt Cafe in nearby Martin Place. Some of them have been forced to hold an Islamic flag at the windows.

Opera House completely evacuated

— Mark Serrels (@Serrels) December 14, 2014

Police closed off Martin Place between Macquarie and Elizabeth Streets, Martin Place train station was also shut down.

Martin Place in the CBD is home to several prominent buildings, including New South Wales Premier Mike Baird's office, the Reserve Bank of Australia, Westpac Bank and the Commonwealth Bank headquarters as well as the US embassy and the Seven Network.

The Supreme Court, Sydney Hospital, State Library of NSW, and NSW parliament were also in lock-down.

"All my thoughts and prayers are with those members of the public affected by the situation in Martin Place and the NSW Police who are trained to deal with these events," Mr Baird said.

"I have spoken to Police Commissioner Andrew Scipione and have full confidence the NSW Police are working effectively to resolve the situation."

The federal government denied reports the airspace over the Sydney CBD had been shut down.

Construction workers gather in front of #Sydney Opera House after evacuation: #sydneysiege

— BBC Breaking News (@BBCBreaking) December 15, 2014

"There are choppers in the air and air traffic is being rerouted according. At this stage no impact on the air traffic network," a spokesman for Deputy Prime Minister Warren Truss said.

Opera House remains in lock down. Reports of "suspicious package" appear unfounded.

— Anthony Klan (@Anthony_Klan) December 15, 2014

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