Chinese police were called to the Ruijin Hospital on Saturday morning following reports of a man wielding a knife.
Videos on social media showed chaos as visitors clambered under turnstiles to get out of the hospital while doctors were seen running out with their patients, some in wheelchairs and one on a mobile bed.
A long trail of blood was seen on the marble surface of a flight of stairs in one video.
“It’s very shocking,” said a Shanghai resident who had arrived for a check-up just after the hospital was sealed off, declining to give her name. “This is very despairing. What has happened to this society?”
Reports of patients attacking medical staff are quite common in China with hospitals facing problems including touts keep up an illegal trade in appointment tickets to long queues to see doctors.
Local police said the man was using a knife to hold a crowd of people hostage on the seventh floor of the building.
They said they opened fire when he threatened to harm his hostages “subduing him” in the process.
None of the wounded is believed to be in a life-threatening situation and the incident is being investigated, the police said.
The hospital has been cordoned off and all appointments cancelled and an investigation has been launched.
It comes after a man was arrested on Monday after going on a stabbing spree in the city’s downtown Jingan district.
