At least two of them were injured when the large tree in Hyde Park crashed to the ground across a footpath and onto a busy street about 3pm on Friday.
City of Sydney officials insist the trees had been inspected as part of routine public safety practices as recently as July, adding they would do so again once the weather cleared.
The first police officers on the scene frantically combed through a sea of branches and foliage to determine if anyone had become trapped.
Emergency services said no one appeared to have been seriously injured in the incident.
Two people suffering minor injuries were transported to the nearby St Vincent's Hospital for treatment, a NSW Ambulance spokesperson said.
The tree, on the park's edge near St James station, appeared to have split in two before crashing across the nearby footpath.
A witness said pedestrians were lucky to escape more serious injuries from the falling tree. (Rhett Watson/AAP PHOTOS)
Two people were hit by the branches and knocked to the ground while onlookers ran to their aid, according to one witness.
The man, who identified himself as Chris, said he was walking along Elizabeth St when he heard the crack of the tree and saw it crash on to a woman.
"There was a gust of wind and the tree has just fallen," he told AAP.
"A lady was in the middle of it. If she had been a few metres back or a few metres forward it would have ended a lot worse.
"But she walked away with a couple of scratches, so she got really lucky. It's such a high traffic area but everyone got away, luckily."
At least three ambulance crews were among emergency services at the scene, where police diverted traffic as the tree blocked two lanes of southbound traffic.
People were warned to stay away from the park's trees as winds swept though the city. (Steven Saphore/AAP PHOTOS)
A City of Sydney spokeswoman said the council was closing Hyde Park, with crews on site cleaning up the area.
"There are around 50,000 trees on land managed by the City of Sydney, all of which are inspected annually by qualified arborists," they said.
"Any required maintenance work is carried out soon after the inspection ... trees in Hyde Park were last inspected in July 2024."
Police rescue crews were considering whether to chop the tree into pieces in order to clear the road.
Staff from the nearby Sheraton hotel ran across to help victims and search for anyone else who had been injured.
Onlookers were warned to stay away from other trees out of fears they could also fall.
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