City police spokeswoman Cyndi Barrington said the victim, Steven C. McKinney, 24, described as a professional climbing instructor, "climbed up the utility pole, came into contact with live wires, accidentally electrocuted himself and was knocked to the ground," the Minneapolis Star Tribune reported.
"The transmitter blew up, and power was knocked out to that area," she said.
McKinney was in critical condition, a spokeswoman at Hennepin County Medical Center said.
Jason Noble, operations manager for indoor climbing venue company Vertical Endeavors, told the newspaper McKinney, who grew up in Plymouth and lives in Minneapolis, has been a climbing instructor at the St. Paul company's downtown Minneapolis location the past six months.
Kayline Graff told the Star Tribune she had talked with McKinney and another man from a window of her residence about 1:30 a.m. shortly before the incident.
Soon after, she said, "I heard a huge explosion with these little subsequent explosions."
"His friend was yelling at me to get water, and I was yelling out the window, 'Are you all right?'"
Graff said she went outside and "saw a ball of fire, which I thought was something else, but it was an actual body. Both his arms were burned up. The shirt was burned off his body. He was bleeding from the mouth."
McKinney's mother, June McKinney, told the newspaper her son had burns over 30 percent of his body.
"He can open his eyes," she said. "He can squeeze a hand. It looks like he is going to make it."