“Our investigation will be to try and determine whether the driver was paying enough attention and why he failed to see the young boy.
“The lights are operating as far as we can tell, they are operating correctly.”
An off-duty police officer stopped to assist the child, who was treated at the scene before being rushed to hospital with serious injuries. He remains in a critical condition.
The father was not injured.
The driver of the van – a 29-year-old man from Clyde – was arrested at the scene.
He was interviewed and released pending further inquiries.
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