A woman was taken to hospital in critical condition after she was struck by a cab on the sidewalk near Elgin and Somerset streets Thursday morning.

The collision happened just after 9 a.m. 

When paramedics arrived, the woman, who is believed to be in her 60s, was in cardiac arrest and suffering from head injuries and multi-system trauma.

Paramedics managed to restart her heart and took her to hospital, where she was listed in critical condition, according to paramedic spokesperson Marc-Antoine Deschamps.

"At 9 o'clock in the morning on Elgin Street the sidewalks are usually quite full of pedestrians, and it is outside of a bank ... so it could have been much, much worse than it is," said Ottawa police Const. Kevin Bradford in an interview at the scene.

Cab driver in serious condition

The driver of the cab, a man in his 50s, was suffering from "medical issues" and was taken to hospital in serious condition, Deschamps said.

Ottawa police Const. Kevin Bradford collision unit pedestrian struck Elgin Sept 14 2017

Ottawa police Const. Kevin Bradford said investigators will be following up on whether a medical emergency may have played a role in the crash. (Elise von Scheel/CBC)

The Ottawa police collision investigation unit is handling the case.

"We have been made aware that there could have been a medical emergency. We're not sure exactly what form of medical emergency, whether it was cardiac ... and that's something that we all need to look into at this point," Bradford said.

"There are two people in hospital right now who are both seeking medical attention, so we will make sure to follow through on all the aspects that we can."

Elgin Street was closed from Somerset to Cooper streets and wa expected to remain closed for several hours, police said.