The first crackling call over police radios hinted at potential disaster around 1:18 a.m. Tuesday – a massive cargo vessel had lost steering control and engine power in the Patapsco River and was adrift, bearing down on the Francis Scott Key Bridge.

In those frantic next 90 seconds, a flurry of responses filled the airwaves as officers raced to the historic double-deck bridge spanning Baltimore’s rowhouse-lined harbor. Their mission was urgently clear – stop all vehicle traffic from entering the bridge immediately in both directions.

“I’m about to drive onto the bridge to get the construction workers off,” one officer broadcasted just after 1:30 a.m., having arrived on the scene.

But it was already too late. Powerless against the river’s powerful currents, the 985-foot long, 107,000 gross ton container ship Dali had become a blazing metal leviathan. It smashed into one of the bridge’s support pillars at an estimated 9 mph with cataclysmic force.

“The whole bridge just fell down…the whole bridge just collapsed,” that same panicked officer radioed moments later, his words barely audible above the thunderous cacophony.

In a matter of splitstream seconds, a large section of the vital Interstate 695 link had crumpled nearly 100 feet into the Patapsco River below in a horrifying tangle of fallen roadway, twisted steel, shattered concrete and scattered debris.

When the dust settled in the inky predawn darkness, a dire situation quickly became grimly apparent – at least eight people were unaccounted for, feared swept into the turbulent waters along with the roadway’s sheared off vehicles.

Among the missing were six immigrant construction workers – laborers from Guatemala, Honduras and Mexico including 34-year-old Maynor Yassir Suazo Sandoval. They had been toiling overnight to repair potholes on the aging bridge’s 97-year-old deck when the unthinkable occurred.

“This was so completely unforeseen,” said Jeffrey Pritzker, an executive at their employer Brawner Builders. “We take such great pride in safety…One would not know what to do.”

For hours after the catastrophic impact, an urgent multi-agency rescue operation was launched spanning air, land and sea. Helicopters swept searchlight beams over the choppy waters as boats and dive teams desperately scanned the massive debris field scattered across the shipping channel’s powerful currents.

Ultimately, an exhaustive hours-long effort located just two survivors amid the wreckage – both were rushed to hospitals, with one treated and released. But for the six remaining construction workers from the crew, a grim reality set in as the agonizing night wore on. They were still missing, their life rafts unnervingly unoccupied, and presumed deceased by their employer.

“You can see the pain etched on their faces,” said Father Ako Walker after meeting with victims’ loved ones during an emotional vigil held overnight. “It is a horrifying, unspeakable tragedy.”

With the hazardous dive operations halted overnight due to fatigue and dangerous conditions including the debris, poor visibility and strong currents, a solemn recovery mission is set to commence at first light Wednesday. Teams are bracing to locate and retrieve the bodies of the six unaccounted for immigrant workers.

While the precise cause remains under urgent investigation by the National Transportation Safety Board, U.S. Coast Guard, and other agencies, officials have indicated the deadly incident appears to have been an awful accident rather than an intentional act.

The Singapore-flagged Dali had been traveling from the Port of Baltimore when it inexplicably veered off course in the restricted shipping channel, slamming into the bridge’s underbelly with catastrophic results. Despite efforts by local maritime pilots to regain control of the wayward vessel, it struck with staggering force.

For a stunned Baltimore and nation grappling with the shocking images of the crumpled span splayed across the harbor, the tragic scene serves as a horrifying reminder of the fragility of even our most vital infrastructure. Horrified witnesses describe a cacophony of sounds – grinding metal, thunderous booms, shrieks of shearing steel.

“It was a resounding boom that rocked the earth and made my windows shudder,” said area resident Donald Heinbuch, one of the first to reach the scene. “It was just an absolutely sickening feeling, knowing cars had to go down with that bridge.”

As shoulders sag under the weight of profound community anguish, many are also hailing the awe-inspiring life-saving heroics of first responders as a beacon of inspiration and humanity amid the unthinkable disaster.

Thanks to the clearing of vehicles from the bridge in those final fleeting moments before impact, authorities say an even greater loss of life was averted. Heroic police efforts quite likely saved numerous motorists from a horrifying plunge into the inky waters below.

“Literally by being able to stop cars from coming over the bridge, these people are heroes,” proclaimed Governor Wes Moore in the disaster’s wake. “They saved lives last night.”

One video captured the chilling scene as the ship bore down, nudging aside ice chunks and hurtling toward the span as traffic continued across the deck – oblivious to the imminent calamity. Only after the gut-wrenching impact did brake lights flare, revealing the unthinkable void ahead where the roadway had stood seconds before.

For the huddled masses lining the railings hours later, the crumpled wreckage stretching across the harbor stood in garish defiance. Where a proud architectural icon had carried over 12 million vehicles across the water each year, now only sheared off remnants remained jutting skyward at haunting angles amidst the debris field.

With shipping traffic indefinitely suspended in the closed 50-foot deep channel, the economic impacts of the catastrophe could prove far-reaching for the Port of Baltimore and industries all along the U.S. East Coast reliant on this critical maritime artery.

But for now, the urgent focus remains squarely on intensive recovery efforts at the scene and providing solace to those shattered families left desperately grasping for closure, their profound anguish etched in hushed sobs.

As the sorrowful work continues, officials vow to leave no stone unturned in uncovering the fateful decisions and potential negligence that inexplicably turned a routine cargo transit into a night of unfathomable tragedy for Baltimore.

Looming overhead, the shattered remains of the once-mighty bridge will serve as a towering memorial to the lives lost, the heroes forged in crisis, and the resilience of a community thrust into unimaginable heartbreak. But still the haunting question lingers – how could such a catastrophic failure unfold in just a matter of mere splitstream seconds?