Pedestrians hit by car in Sydney

Seven people have been injured with one woman in a serious condition after a car ploughed into pedestrians on a busy street in Sydney's northern suburbs.

The male driver is believed to have suffered a medical episode when he crashed into the footpath out the front of a restaurant on Victoria Avenue in Chatswood on Saturday afternoon.

Six people were taken to Royal North Shore Hospital, with a 22-year-old woman in a serious condition.

"CareFlight's specialist doctor and critical care paramedic ran to the scene, pushing their way through crowds to reach the most seriously injured pedestrian, a woman in her 20s," CareFlight said in a statement.

A 16-month-old girl is one of the injured but is in a stable condition, a Northern Sydney Local Health District spokeswoman told AAP.

The incident was not a deliberate act and the male driver remains at the scene assisting officers, police said in a statement.