Police and Peco responded to the 500 block of Hermit Street in Philadelphia's Roxborough section after many people reported that they saw, heard, and felt an enormous release of energy.
It was around 10:15 a.m. when the witnesses say they first saw a flash then heard an explosion.
"It was really brilliant, like it lit up the sky," said Joe Brach.
Anthony Amadio was sitting at his kitchen table when two windows blew in, cutting his head. In all, more than a dozen of his windows were shattered.
Amadio tells us, "I was in Vietnam in 1969, and it was about like that. I thought I was hit with a rocket… that's how intense the explosion from whatever it was - the lightning, the tree, or the transformer – I'm not sure."
At least eight houses lost windows. At the time of the incident Pat Amadio was few blocks away on Ridge Avenue going to the bank when she looked up.
"It wasn't a bolt, it was a big ball," Pat said, adding the bright ball then just disappeared.
It is still unclear what happened, but one possibility officials are looking into is that lightning may have struck a PECO transformer in the neighborhood, causing the explosion.