A gunman took over 30 people hostage at a busy cafe located not far from the Indian consulate in this Australian city.
The dramatic siege took place in Sydney's bustling central business district, days ahead of Christmas.
The hostages were seen standing with their hands up at the windows of the Lindt Chocolate Cafe in Martin Place. There was also a black and white flag, believed to be a jihadi flag, being held up in a window, Xinhua reported.
Heavily armed police responded quickly and surrounded the building. There were conflicting reports about the number of hostages. While one account put the number of hostages at 20, another account said that there were over 30 hostages.
Three hostages managed to flee, police said and added that nobody was harmed in the initial hours.
Australian Prime Minister Tony Abbott called for calm as security personnel tried feverishly to tackle the siege.
Thousands of workers across the city have been sent home early and some of the city's major buildings including the Opera House, the State Library, Channel Seven, the New South Wales parliamentary executive offices, the NSW Supreme Court's criminal courts, the Downing Centre and several city legal chambers were evacuated.
The Indian consulate is located less than a kilometre away.
Abbott said police "are currently responding to a reported hostage taking incident in Martin Place in Sydney".
The National Security Committee of the Cabinet has also been convened for briefings on the situation.
The prime minister described it as a "deeply concerning incident, but all Australians should be reassured that our law enforcement and security agencies are well trained and equipped and are responding in a thorough and professional manner".
In New Delhi, Indian Prime Minister Narendra Modi expressed concern over the siege.
"The incident in Sydney is disturbing. Such acts are inhuman and deeply unfortunate. I pray for everyone's safety," the prime minister said in a statement.
New South Wales (NSW) police commissioner Andrew Scipione said police were yet to make contact with the the one or more offenders who laid seige at the Lindt Chocolat Cafe, the Sydney Morning Herald reported.
"We are still determining what it is that may well be the motivation. We are not in a position to determine where the individual is from," the paper quoted Scipione as saying.'
Three hostages flee from Sydney cafe
Three people fled to safety from a cafe where over 30 people are being held hostage at gunpoint in this Australian city.
Three hostages have made it out of the cafe at Martin Place, Deputy Commissioner Catherine Burn was quoted as saying by Sydney Morning Herald.
An armed man Monday took the people hostage inside the Lindt Chocolat Cafe in Sydney's central business district.
Australian PM Calls For Calm Amid Sydney Hostage Situation
Australian Prime Minister Tony Abbott called for calm after a gunman took up to 12 hostages in Sydney's city center Monday morning.
"New South Wales (NSW) Police and the Australian Federal Police are currently responding to a reported hostage taking incident in Martin Place in Sydney," Xinhua quoted Abbott as saying.
"I have spoken with NSW Premier Mike Baird and offered him all possible Commonwealth support and assistance."
"The National Security Committee of the Cabinet has also convened for briefings on the situation," said the prime minister.
"This is obviously a deeply concerning incident, but all Australians should be reassured that our law enforcement and security agencies are well trained and equipped and are responding in a thorough and professional manner," he added.
Abbott also confirmed that the federal government would provide further updates as further information becomes available.
Canada Watches Australian Situation
Prime Minister Stephen Harper and other Canadian government officials were closely watching what was being described as an apparent hostage taking in Australia's largest city.
"Canada's thoughts and prayers are with our Australian friends," Harper tweeted.
Police in Sydney said they were dealing with "an armed incident," but wouldn't confirm hostages were being held inside the Lindt Chocolat Cafe in Sydney.
Television footage shot through the cafe's windows showed several people with their arms in the air and hands pressed against the glass.
TV footage showed two people inside the cafe holding up what appeared to be a black flag with white Arabic writing on it.
Australian Prime Minister Tony Abbott refused to speculate on whether the incident was linked to terrorism.
Foreign Affairs Minister John Baird tweeted late Sunday that he was in touch with his Australian counterpart Julie Bishop.
"We continue to monitor the situation in Sydney closely," Baird tweeted.
The situation in Australia came nearly three months after Harper and Baird were at the centre of a crisis that gripped Ottawa, where a lone gunman killed a Canadian soldier and then stormed the Parliament Buildings before being gunned down by security.
A spokesman for Baird said late Sunday that the government is in close contact with its diplomatic posts in Australia.
"We urge all Canadians in Sydney to use extra precaution and limit their movements as authorities handle this situation," Rick Roth said in an emailed statement.
"We have offered Australia any assistance Canada can provide."
Canada has a consulate in Sydney that is roughly one kilometre from where the cafe involved, but Baird's office said all staff at the mission are safe and accounted for.
Modi Expresses Concern Over Sydney Siege
Prime Minister Narendra Modi Monday expressed concern over the Sydney cafe siege incident and described it as "deeply unfortunate".
"The incident in Sydney is disturbing. Such acts are inhuman and deeply unfortunate. I pray for everyone's safety," the prime minister said in a statement.