By Matt Petrillo

PHILADELPHIA (CBS) — Two homes collapsed in South Philadelphia on Tuesday. Philadelphia police say there were no injuries.

Security video from the next door home first obtained by Eyewitness News captured the collapse.

“It just sounded like an earthquake,” one witness said.

Heart-pounding moments as two homes collapsed on the 700 block of Mercy Street in South Philadelphia Tuesday.

Flying debris landed on Lindsey Tyrrell’s parked SUV.

“That’s a bummer, I just bought it last month. Yeah, it’s OK. I was more concerned that someone was stuck in the house,” Tyrrell said.

A crew from Eastern Contracting was working inside one of the homes earlier Tuesday. Neighbors say they were probably on lunch break when the collapse happened.

“I mean, an hour earlier they would have been working in the basement so just lucky that nobody got hurt,” neighbor David Mostoller said.

Video shows someone entering the screen from the left side of the sidewalk before running away as the building falls.

Philadelphia’s License and Inspections Office says Eastern Contracting did have a work permit. But officials say it looks like the front walls of the home crews were working on was the first to collapse, forcing the home to crumble.

In the process, it pulled down the vacant home next door.

All of it alarmed those who live nearby.

“Welcome to the neighborhood, we just moved in. So this is pretty incredible,” neighbor Joe Shelinsky said.

Electricity is shut off on the block. L&I is still investigating what led up to the collapse.