A worker was electrocuted Wednesday while making repairs inside a sign at a bank in Centerville, authorities said.

Thomas Michael Gamboni, a 47-year-old master electrician, died about 11:30 a.m. outside Central Bank, just north of Anoka County Road 14 and west of Interstate 35E, authorities said.

The sign was being repaired because the upper portion of it that displayed the bank's name was not lighting, said Centennial Fire District Chief Jerry Streich.

Gamboni had "entered through a small access hole, while another worker was in the bucket," Streich said. Gamboni was electrocuted while inside the sign and "looking at a control box in there," Streich said.

Firefighters cut a hole into the sign to reach Gamboni, who was unresponsive, and lowered him in an aerial apparatus 15 to 20 feet to the ground, where medical personnel attempted to revive him, the chief said.

A work truck from L & D Sign in Stillwater was at the bank at the time of the electrocution. An employee there said the company was not commenting on the incident.

Gamboni's younger brother, Troy, was shaken when he learned about the accident. "He was my best friend," Troy Gamboni said. "He had a big heart under that tough-guy persona. He was a super hero. He was one guy you always looked up to. He would do anything for anyone."

Investigators were on the scene into the afternoon trying to determine what led to the man's death. The state Occupational Safety and Health Division also was investigating.

Paul Walsh • 612-673-4482