A terrifying hostage situation began to unfold just before 10am at the Lindt Cafe in Martin Place.
Two hours later, authorities are being told to avoid the CBD and there are major flow-on effects and delays, especially to public transport, as police enforce a lockdown in the CBD.
Business Insider will keep updating the details as they come to hand.
UPDATE: Police have asked people in offices facing Martin Place to stay indoors until notified to leave. All other CBD workers should proceed home as normal.
ALL PERFORMANCES AT THE OPERA HOUSE HAVE BEEN CANCELLED.
HERE ARE THE ROAD CLOSURES
Here is the exclusion zone:
Martin Place is closed, cutting off Castlereagh and Elizabeth streets. Various road closures are in place and more may occur at short notice.
There are an estimated 40 people inside the Lindt Cafe being held hostage.
The nearby Westpac Bank and Channel Seven offices were evacuated. Westpac, ANZ and the Commonwealth Banks have all closed their branches in the city. Telstra has also shut its stores.
Due to the police operation in Martin Place Sydney, 12 Westpac branches in Sydney CBD will be closed for the rest of today.
— Westpac Bank (@Westpac) December 15, 2014
Due to the #MartinPlaceSeige we are taking the precaution of closing our Sydney CBD branches, please let us know if you need any assistance.
— ANZ Australia (@ANZ_AU) December 15, 2014
ANNOUNCEMENT: We have closed all Sydney CBD branches due to current police operations.
— CommBank (@CommBank) December 15, 2014
The Sydney Opera House is closed and evacuated after a suspicious package was found down there. The stairs and forecourt are blocked off.
All courts in the CBD are in lockdown with heightened security.
NSW parliamentary executive offices and State Library are reportedly in lock down.
The US Consulate, not far from the cafe has been evacuated. The consulate has also warned US citizens in Sydney to be extra vigilant.
There are other security measures in place it seems
Town Hall station underground walkway to George St closed. Need to exit via stairs on Town Hall side. #sydneysiege
— aptronym ® (@aptronym) December 15, 2014
All southbound traffic on the Sydney Harbour Bridge is being diverted via the Western Distributor. There is no access to the Cahill Expressway, York Street or Harbour Street.
There is no access for northbound traffic to the Cahill Expressway. All motorists are being diverted into the Sydney Harbour Tunnel. Northbound motorists on the Western Distributor cannot access King Street.
The Sydney Harbour Tunnel remains open.
Public transport passengers are able to use their tickets across all modes of transport in the Sydney CBD.
Buses in the Sydney CBD are diverting. Expect extensive delays. Buses are following the direction of police on site and may change their route at short notice.
Northern Beaches buses are now terminating at North Sydney railway station.
Buses entering the city from the Eastern Suburbs are terminating at Hyde Park.
Buses travelling to the city across the Sydney Harbour Bridge are terminating at Wynyard due to a police operation
Buses travelling towards the Sydney CBD from the south are terminating at Central Station
Buses that operate on Elizabeth St between Market St and Circular Quay are terminating at Hyde Park. They won’t travel to Circular Quay.
The Martin Place station is closed. Trains have resumed operating on the T4 Eastern Suburbs & Illawarra Line however services are not stopping at Martin Place
— NSW TrainLink South (@TrainLinkSouth) December 15, 2014
Flights have been rerouted away from the CBD, but there are no reports of delays. The airport is operating as normal.
BREAKING NEWS: All Qantas flights are diverting around Sydney CBD but are operating as per schedule at this stage
— Qantas (@Qantas) December 15, 2014
UPDATE: Qantas says it will help people who miss flights as a result of the traffic.
After initially instigating surge pricing for hire cars in the city, smartphone app Uber had a major change of heart and is now offering free rides out of the CBD to customers.
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