"[It was] a five man stone or a five man block which indicated that you would need four to five people to life it and set it on a wall, and we have done stones like that and built with stones like that, so I knew we could lift it by hand," Potter said.
"I think that was the main concern – can we lift it off the boy?"
Authorities responded to 325 Little Harbor Road after a distress call about a 2-year-old trapped under a pile of rocks.
When officers arrived, they found the boy pinned between large slabs of stone.
The boy had been playing on top one of the stone slabs with his grandfather when the slab he was standing on dislodged. The child fell forward and was trapped by the slab, which came to rest on his head.
The stone slabs are being used to build a foundation for a seawall and each slab is estimated to weigh several hundred pounds.
The situation was highly delicate, police said, because one of the stone slabs was resting on the child's head, and could have given way at any moment, putting the child at risk of sustaining the full weight of the stone on his head.
After a coordinated effort by police and firefighters, rescuers freed the boy in about nine minutes.
The child's parents were able to keep him calm as first responders worked their way around the stone slabs and rescued him.
The child was first given emergency medical treatment at the scene then transported to the Portsmouth Regional Hospital where he was treated for non-life-threatening injuries.