A woman and child have been seriously injured after being hit by a car during school drop-off hours in Sydney.

The eight-year-old boy and the 35-year-old woman were walking near Wollongong Rd in Arncliffe when they were hit by a car about 8.45am on Monday.

Police rushed to the scene and found the pair seriously injured.

NSW Ambulance paramedics treated them before they were taken to Sydney Children’s Hospital and St George Hospital, respectively.

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Police said they are now speaking with the driver, a 43-year-old woman.

An investigation into the cause of the crash is continuing.