A chilling tragedy unfolded at Brown University, claiming innocent lives while warning signs were tragically overlooked.

Disturbing details have emerged about a mass shooting on December 13 at Brown University, where janitor Derek Lisi repeatedly alerted campus security to a suspicious man pacing the halls, the Daily Mail reported.

Lisi observed Claudio Neves Valente, the alleged shooter, lingering near the Barus and Holley engineering building on roughly ten occasions since early November. His gut told him something was wrong, and he acted on it with urgency.

Unheeded Alerts in the Face of Danger

“He’d been casing that place for weeks,” Lisi told the New York Times, capturing the eerie persistence of Valente’s behavior. If only those words had sparked swifter action, the outcome might have differed.

Lisi reported the odd activity twice to campus security, even following Valente once, only to see him dart into a restroom to evade scrutiny. Event Staffing Services, a Brown contractor, confirmed receiving a report but washed their hands of any duty to investigate.

Meanwhile, the campus remained vulnerable as Valente, a former Brown graduate student from 2000 to 2001, continued his unsettling reconnaissance. His lack of current ties to the university offered no comfort when bullets flew.

Tragic Losses and a Second Witness

The shooting claimed the lives of two students, Mukhammad Aziz Umurzokov, 18, of Virginia, and Ella Cook, 19, of Alabama, while wounding nine others in a lecture hall. A promising neurosurgeon and a vibrant sophomore, both snuffed out by senseless violence, leave a void no policy can fill.

Another voice, a homeless man named John, also noticed Valente’s bizarre behavior near the engineering building hours before the attack. His sharp eye caught clothing unfit for the weather and a peculiar game of evasion around a gray Nissan with Florida plates.

John’s tip, amplified through Reddit posts, broke the case wide open, leading police to identify Valente via surveillance from over 70 street cameras. Rhode Island Attorney General Peter Neronha praised him, saying, “He blew this case right open,” a rare nod to street-level vigilance.

A Broader Trail of Violence

Investigators believe Valente didn’t stop at Brown, fatally shooting MIT professor Nuno F.G. Loureiro, also Portuguese, two days later at his Massachusetts home. Shared academic history in Portugal from 1995 to 2000 hints at a deeper, darker motive yet to be unraveled.

Valente, 48, was found dead on Thursday evening in a New Hampshire storage unit, a self-inflicted gunshot ending his rampage. Police confirmed he acted alone, but the question of why lingers like a bitter fog.

His path from Brown student on a visa to legal permanent resident in 2017, with a last known address in Miami, raises hard questions about tracking and accountability. President Trump’s suspension of the green card lottery program in response signals a firm push to tighten such gaps.

Lessons in Vigilance and Loss

The heartbreak of losing young lives like Ella and Mukhammad stings all the more, knowing alerts were raised and ignored. Campus safety isn’t just a checkbox; it’s a duty that demands real teeth, not hollow protocols.

John’s grit in speaking up, despite his own struggles, shames the bureaucratic shrug that let Valente slip through. If a man on the margins can see danger, why can’t those paid to protect act with equal clarity?

This tragedy at Brown University isn’t a call for panic but a demand for systems that honor the instincts of everyday guardians like Lisi and John. Let their voices echo until no warning goes unheard, no life is needlessly lost.