Two teen-age brothers installing a television antenna atop an aluminum roof were electrocuted when the device fell into several high-voltage power lines, authorities said. Christopher Cacioppo, 16, and Dominick Cacioppo, 19, died shortly after the noon accident at their home in the 9500 block of East Woodford Street in Pico Rivera, Sheriff’s Deputy Steven Lee said. The boys had climbed atop an aluminum roof to secure the television antenna, Lee said. As they worked, the antenna fell into nearby power lines and the brothers were electrocuted, he said. Christopher was taken to Beverly Hospital in Montebello, where efforts to revive him failed. His brother died at Whittier Presbyterian Hospital, Lee said.