Well over 100 attendees at an Englewood 4th of July party apparently didn't realize the house was on fire until a passerby dialed 911, neighbors said.
The good Samaritan said she "happened to be walking my grandson" on West End Avenue when she "saw the left side of the house on fire" around 10:30 p.m. Saturday.
"There were a lot of drunk people -- like, 150," a witness said. "Nobody noticed."
No serious injuries were reported.
Police charged Robert Ferrarelli, 20, with aggravated assault on a police officer, making terroristic threats during a state of emergency, rioting and resisting. He was released pending a court hearing.
City and Tenafly police and Bergen County sheriff's officers joined firefighters from Englewood, Hackensack and Teaneck at the scene.
Although authorities hadn't officially determined the cause, they noted that spent firework casings were found on the outside of the house where the two-alarm fire broke out before spreading to the second floor.
Area residents said they've often complained about fireworks on their street.
Click here to sign up for Daily Voice's free daily emails and news alerts.