What to Know A mysterious boom rattled homes in South Philadelphia early Tuesday. People as far away as New Jersey also heard something.

It wasn't clear where the sound came from.

NBC10 will continue to seek answers as to what caused the strange sound.

What went boom in the night? A mysterious loud noise shook some people in Philadelphia from their sleep early Tuesday.

The boom rattled some South Philadelphia homes just before 2 a.m. People turned to social media to ask their neighbors if they heard it too. Other people called police to report the sound. Some people described it as sounding like an explosion.

“This was just really loud, it was just so deep, it couldn’t have been normal,” Ren Pags, who heard the sound in the area of 12th and Oregon streets, said. “It was almost like the fireworks, the real big ones that sparkle at the end, the real deep boom.”

Chris Galvin thought there was a car crash in front of his house.

"It felt like it shook my entire house," the South Philly resident said. "Sure enough, I didn't see anything so I took to social media to see if anyone else was searching for this loud noise."

Some people reported hearing some sort of loud noise as far away as New Jersey and Kensington.

NBC10 reached out to police and firefighters but got no answers about what caused the sound. There were no reports of any blast.

The military didn't respond to NBC10's request to see if there were any air drills overnight. The U.S. Geological Survey had no reports of an earthquake in the area Tuesday morning.

Did you hear it?

NBC10 will continue to seek answers as to what caused the strange sound.