The two officers, a 38-year-old senior constable and a 32-year-old probationary constable, had been sent to the intersection of Narellan and Kellicar Roads at Campbelltown to direct traffic while the lights were flashing amber, police said.

The officers were walking towards the intersection in yellow reflective vests when a car hit two other cars, pushing one of the vehicles up onto the footpath and into the two women, at about 8am.

The impact left the 38-year-old with facial injuries, while the 32-year-old sustained facial and leg injuries, police said.

Both women were taken to Liverpool Hospital.

The female driver of one of the cars hurt her hand. A boy in the car with her was unharmed, police said.

No one else was hurt.