A 24-year-old Toronto woman is in hospital with critical injuries after she tripped and fell backwards into the path of a streetcar.

The woman, whose name has not been made public, was out early Sunday morning enjoying the city's Nuit Blanche art event when she lost her balance, fell and became trapped underneath the streetcar.

The incident happened as she was crossing Spadina Avenue at College Street around 3:40 a.m. She was rushed to hospital in critical condition with head trauma.

"We couldn't help her, she was way under," witness Gary Pieters told CTV Toronto. "She was under the streetcar. Like if you looked on the street, you would have seen one of her shoes."

Several people who saw the incident rushed to help the woman and try to keep her calm. Emergency crews worked quickly to jack-up the streetcar and get underneath.