A siege is taking place at a cafe in Sydney’s central business district.

Police are advising people to steer clear of the Lindt Chocolat Cafe in Martin Place.

Customers and worker’s faces are pressed up against a shop window inside the cafe.

Martin Place has been shut down and scores of police are surrounding the building after the alarm was raised about 9.45am.

Workers in nearby buildings, including the Seven Network, have been ordered to evacuate the area.

NSW government offices, including Premier Mike Baird’s, are in the vicinity of the cafe.

Two women, whose faces are pressed up against the window, appear to be holding up the flag.

Police have closed off Martin Place between Macquarie and Elizabeth Streets, and Martin Place train station has been cleared.

Police have cordoned off the area to about 150m and a special police operations unit is outside the building.

Two women, whose faces are pressed up against the window, appear to be holding up the flag.

Police have closed off Martin Place between Macquarie and Elizabeth Streets, and Martin Place train station has been cleared.

Police have cordoned off the area to about 150m and a special police operations unit is outside the building.

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