As Sydney continues to , a group of residents have been dubbed "heroes" for apprehending the knifeman.
The situation began just after lunchtime when a man was seen on the streets of the CBD after allegedly stabbing a woman.
Briton Paul O'Shaughnessy, 37, told reporters he and his brother Luke, 30, were working in their office nearby when they heard the commotion.
"Luke, my brother popped his head out [the window] and said ... 'there's a guy holding a knife, he's just jumped on a bonnet, you can see blood, mate come on', he said 'this is it'."