A witness to a Christchurch teen who received an intense electric shock while climbing a power pylon says the boy suffered serious injuries.
The teenage boy remains in a critical condition in Christchurch hospital.
Emergency services were called to Ashtead Lane in Sockburn at 7:40pm Friday.
Eyewitness Josh Phillips said the teen was visibly on fire for a minute after the electric shock.
"So basically the first initial sound was just this big bang.
"And then you could literally see flames. He literally blew his shorts off, like they'd exploded. That's how much electrical current went through this guy.
"He was on fire for about a minute straight."
Phillips said when fire crews rescued him, there were fears about the state of his body temperature lowering rapidly.
"He was complaining a little bit before ... that he was cold and I feel like there might have been a fear that he could possibly be going into cold shock because it was quite windy.
"He went from speaking to not speaking for about 10 minutes and I think that's when the crew kind of started ramping things up a bit.
"He was probably up there for about two hours."
Phillips said a group of teenagers were at the scene crying over the boy.
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