Residents hurled rocks and bottles at Detroit firefighters as they extinguished a suspicious blaze in a vacant house Friday night, accentuating a wild 24-hour period in which fires broke out in 25 homes, nine cars, a school and an apartment building.

Of those 36 fires, at least 29 were suspicious.

Shortly before 9 p.m., firefighters arrived at a vacant house fire at 14519 Robson. Soon after, residents began chucking bottles and rocks at the firefighters and their rigs on a block devoured by blight.

“I need as many police as possible,” Chief 7 told dispatchers. “I have civilians attacking firefighters and FEOs, throwing bottles, rocks and whatnot.”

About 10 minutes later, two police cars and a helicopter descended on the area. It wasn’t immediately clear whether the assailants were found.

The first arson fire on Friday broke out inside an occupied house at McKinney and Grayton on the east side at 2:55 a.m. Over the next 21 hours, the fires were relentless, sometimes spreading to neighboring homes.

At 12:35 p.m., a suspicious fire inside a vacant house spread to an occupied home and abandoned apartment building, devouring all three structures at St. John and Ewer in southwest Detroit. Arson is suspected in a fire that damaged Alexander Macomb Elementary School on the east side near Chandler Park at 4:10 p.m.

Between 6:45 p.m. and 8:20 p.m., two fires broke out one block from each other at E. Kirby and Grandy, an area already decimated by arsons and abandonment.

The fires present a significant challenge to a city struggling to curtail a six-decade population decline. The fires are burning out neighborhood cores, accelerating blight and ratcheting up insurance rates.

Here’s a map of Friday’s fires.

View Aug. 29 fires in a full screen map