An investigation is under way and remains in the early stages but it is believed the electrocution happened as the children touched the power line with a pole.
According to reports in the Lancashire post, the children were trying to use the metal pole to retrieve a ball in a pond.
Two other teenagers were not seriously hurt, police added.
The incident happened near Euxton Villa Football Club, near Chorley.
The West Lancashire League club tweeted: “Due to a tragic incident over the weekend please note the ground and the car park will remain closed on Monday 8th March – Our thoughts are with all those affected.”
Inspector John McNamara, of Lancashire Police, said: “This appalling incident has led to the tragic death of a young man and my thoughts are first and foremost with his family and loved ones at this time. The family are being supported by specially trained officers.
“I would appeal to anyone who has any information to get in touch with us by calling 101 and quoting log 1241 of March 6th.”
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