The gunman holding people hostage in a Sydney cafe has been identified as Man Haron Monis, an Iranian refugee who was on bail facing a number of charges, according to the BBC.
The 49-year-old was granted political asylum in Australia and described by his former lawyer as an isolated figure, who was acting alone.
Police say they will maintain central Sydney in lockdown until the hostages are brought out unharmed.
Talks with the gunman continued after nightfall as police ringed the cafe.
A black Islamic flag has been displayed at the window. The number of those held in the Lindt cafe is not clear.
Five people have run from the building, located in Martin Place – a busy shopping area in Sydney’s financial district. It is unclear whether they were released or escaped.
It appears the gunman has used three of the hostages to pass on demands, making them stand beside a black flag and having them make statements to a camera.
Prime Minister Tony Abbott said it was “profoundly shocking” that people were being “held hostage by an armed person claiming political motivation”.
News organisations say he has contacted them to issue demands, which police have urged media not to report.
Mr Monis, who styles himself as a Muslim cleric, is currently on bail for being an accessory to the murder of his former wife and is facing more than 40 sexual and indecent assault charges.
He has also been convicted of sending offensive letters to the families of deceased Australian soldiers.
There are reports that one of his demands is for the flag of the Islamic State militant group to be delivered to the cafe, the BBC’s Jon Donnison reports.