The five-year-old girl had just stepped off her school bus on Hastings Street in Rocky Point, near Wyong, at 3.40pm when she was hit by the truck, leaving her with critical injuries.

Police understand the girl was "quite a distance" in front of the bus when she began to cross the road.

She was "obscured" by the bus, meaning the truck driver did not see her before she was hit.

Police and paramedics were called to the scene and gave first aid to the girl but despite their efforts, she died at the scene.

Seven News reported the girl's mother was waiting to pick her up and witnessed the tragedy, as did other young children.

She reportedly suffered shock and was taken to hospital.

In a statement, police said the driver of the truck was taken for mandatory testing after the crash.

A NSW Ambulance spokesman confirmed paramedics transported two people to Wyong Hospital from the scene.

The tragedy came as students around NSW returned to school on the first day after school holidays.

Vision from the scene showed police escorting students to a second bus to move them away from the crash site.

A police spokespersons aid said a report will be prepared for the Coroner.

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