Police have negotiated with a man for hours after the body of a young woman was found in an alley outside an apartment building in Sydney early on Monday.
A pedestrian made the discovery near Chatswood train station about 6.30am local time, reports the Sydney Morning Herald.
It is understood the woman's injuries were consistent with having fallen from a height.
The apartment building on Brown Street, Chatswood, borders an alley way where the body of the woman, believed to have been aged about 25, was found.
The man is kneeling on an awning above a balcony connected to the apartment complex gym, which is near the top of the high-rise complex.
The awning overlooks the laneway where a crime scene tent conceals the woman's body, which police have been unable to take away while the man remains on the roof.
Fairfax Media claim that a crime scene has also been established inside the gym.
Police and a Korean translator are negotiating with the man, who has been on the awning for several hours.
He is barefoot, with his shoes by his side, and is wearing a white T-shirt with grey tracksuit pants.
Shortly after 11am, the man was still on the roof and appeared to be conversing with police negotiators, while smoking a cigarette. He has also been given bottled water.
She said the police operation involving the man on the roof was secondary to the discovery of the body.
The street, which runs between the Pacific Highway and Railway Street in the Chatswood business district, has been cordoned off.
The police operation was taking place in front of hundreds of office workers, including some in surrounding high-rise buildings overlooking the balcony roof.
One worker said the scene was heartbreaking to watch.
"It sort of makes you feel a little bit sick. It's heartbreaking," he said.
The cordoned area was extended about noon to manage increasing numbers of lunchtime office workers watching and filming the operation.
Brand storytelling agency Filtered Media is on the eleventh floor of an office block adjacent to the operation.
Chief executive officer Mark Jones said the majority of his 33 staff had been sent home in light of the incident.
"We had staff in here from 8am. Unfortunately the tent [concealing the woman's body] is down in the space between the buildings," he said.
"So we look out on residential buildings and normally it's guys doing tai chi..."
Jones said the man on the roof was one floor up from the Filtered Media office.
"The staff were quite upset as you would expect so we sent out a note to say please put down your blinds or go home ... if you're uncomfortable about the whole situation," he said.
"It's pretty confronting."