A mysterious late-night boom echoed across large swaths of Maricopa Friday night, startling residents from Rancho El Dorado to Homestead and lighting up neighborhood social media feeds with one urgent question: What just exploded?

Reports began rolling in just after midnight, with residents in Rancho El Dorado saying the sound was loud enough to wake them from sleep, send dogs into panic and prompt more than a few cautious glances toward back doors.

“My boyfriend and I were getting ready for bed and heard it too,” one resident posted on Facebook. “We’re in Rancho El Dorado.”

Others chimed in from miles away. One resident in The Lakes at Rancho El Dorado said the boom sounded close enough to be “in or around the house,” while neighbors in Homestead described it as “definitely not a firework.”

The Nextdoor app was alight, with posts stacking up rapidly: “That just sounded like a gunshot,” wrote one user.

Another said the noise “woke me up” and prompted them to check security cameras — without spotting anything unusual.

The collective reach of the sound suggested something powerful, or at least something capable of traveling across neighborhoods separated by more than a mile. Dozens of users on the Ring app reported “potential gunshots or explosions.”

“It scared the mess out of us,” wrote a user on the home-security app with a built-in neighborhood alert feed.

The police heard about it, too.

According to Maricopa Police Department spokesperson Monica Williams, officers did respond.

An officer was flagged down by a homeowner who reported hearing the explosion and shared video captured by a rear-facing security camera. That footage shows a loud explosion, immediately followed by a flash of light that appeared to originate near Desert Greens Drive.

Despite the dramatic audio and visual cue, officers who checked the area found no physical evidence of an explosion.

In total, MPD received three calls reporting the noise, Williams said.

For many residents, the unanswered questions felt familiar. Just weeks ago, a late-night blast in the Acacia Crossings neighborhood damaged a community mailbox near Ancon Avenue and Bahia Drive, a separate incident that also sent residents to Ring and Facebook describing what they called “the loudest boom I’ve ever heard.” That incident, too, left more questions than answers in its immediate aftermath.

The mystery lingers, an unexplained punctuation mark in an otherwise quiet Saturday morning.