A gunman has taken several people hostages at a cafe in the Australian city of Sydney.
Pictures on Australian television showed people with their hands up against a window, and a black flag with Arabic writing.
At least a dozen police officers were surrounding the site and the area was closed off.
There were also reports that a person was seen inside the cafe waving an Islamic State flag.
Police confirmed an operation was under way at the shop in Martin Place.
Check back for updates.
