Here are 10 developments in this big story:
The police said at least one armed offender is holding hostages at the Lindt Chocolate cafe in Martin Place, a major shopping and pedestrian thoroughfare in the central business district of the city.
An Infosys employee is said to be among some 30 people trapped in the cafe. The IT company said the employee's family had been informed and it was extending all support to them. (Read more...)
Terrified customers were seen in the morning pressed against a window, holding a flag with writing that appeared to be the shahada, or profession of faith in Islam, and said: "There is no god but Allah; Mohammed is the Messenger of Allah."
Police negotiators are in contact with the gunman described as a man in his late 40s to 50s, wearing a black and white bandanna. Reports suggest the armed offender has demanded to speak to Australian Prime Minister Tony Abbott and an Islamic State flag.
Around six hours after the crisis erupted, five people, including two women, were seen running out of the building. (Read more...)
Major landmarks including the Sydney Opera House were evacuated as the crisis broke out. Banks have shut down their offices.
The US has evacuated its Sydney Consulate located near the cafe; and issued an emergency warning to its citizens. The Indian consulate, about 400 m from the cafe, has also closed down.
Australia, which is backing the US and its escalating action against Islamic State in Syria and Iraq, is on high alert for attacks by radicalised Muslims or by home-grown fighters returning from the conflict in the Middle East.
Prime Minister Narendra Modi tweeted, "The incident in Sydney is disturbing. Such acts are inhuman & deeply unfortunate. I pray for everyone's safety."
The Indian government said queries about Indian nationals would be taken by Deputy Consul General Vinod Bahade at +61 481 453550. (Read more...)
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