Hayden Panettiere's HOA Warned Residents to Call 911 If They Saw Brian Hickerson

Hayden Panettiere's neighbors were once warned to call 911 immediately if they spotted Brian Hickerson on their property ... and TMZ has learned a warning poster with his photo went up after a string of complaints about his alleged behavior.

Mia Terrazas, who lived one door down from Hayden's West Hollywood condo, tells TMZ ... the HOA posted the warning at the end of August 2025 ... urging residents not to let Brian into the building and to call cops if he was seen anywhere on the property.

Mia says the poster came after years of disturbances involving Brian.

She tells us Hayden bought the condo after moving from New York ... and says Brian had been living there for the past two years.

As we previously reported, Brian was arrested in 2020 after cops said he punched Hayden in the face.

He later pleaded no contest to felony domestic violence charges and served jail time.

Mia tells us she was always scared of Brian and believed he was dangerous the whole time he was living with Hayden ... which continued even after the court issued a no-contact order.

As for that warning poster ... Mia says the HOA took it down about a week after it went up. She says she was told Brian was no longer considered a threat.

Mia also spoke with "Inside Edition" ... telling the show she was "terrified" of Brian and called 911 at least half a dozen times over disturbances at Hayden's apartment.

The poster may have come down ... but Mia says her fear of Brian never did.

We broke the story ... Brian was asleep in another room when his brother, Zach, entered their Airbnb in South Carolina on Sunday afternoon and found her unresponsive in an armchair. Hayden was in cardiac arrest, but she was not able to be resuscitated, and she was pronounced dead.