An armed man's thought be holding up to 40 people hostage in a cafe in Sydney.
New South Wales Police say they can't rule out terrorist involvement.
There are reports that up to five people have managed to escape the siege in the central business district.
Hostages can be seen holding their hands up, and Islamic flags have reportedly been hung from the windows
Kathryn Chee works there, and broke down as she described seeing her colleagues held captive:
