A catastrophic terrorist bombing rocked Wall Street at 12:01 p.m. on Sept. 16, 1920 in New York's financial district, killing 38 and seriously injuring 143. The plot was never solved, though evidence led to the Galleanists, an organized group of Italian anarchists. The attack was attributed to post-World War I social unrest, labor struggles and anti-capitalist U.S. sentiment.
It was the worst disaster in New York since the 1911 Triangle Shirtwaist Factory fire, which killed 146 garment workers (and in fact, stood as the city's worst loss of life until 9/11/2001).
Here's how it went down: At noon, a horse-drawn wagon passed by lunchtime crowds on Wall Street and stopped at 23 Wall Street, the headquarters of J.P. Morgan Bank—the busiest corner in the area. Inside the wagon, 100 pounds of dynamite & 500 pounds of cast-iron "sash weights" exploded in a timer-set detonation, sending a kaleidoscope of shrapnel. The horse and wagon were blasted into fragments, but the driver was believed to have escaped.
The 38 victims, who died instantly, were mostly young messengers, stenographers, clerks and brokers. Meanwhile, the bomb caused more than $2 million in property damage and destroyed most of the Morgan building's interior.
Crews cleaned up the area overnight to allow for normal business operations the next day, but in doing so, destroyed evidence that might have helped investigators solve the crime. The Bureau of Investigation and local police scoured the case for three years... but to this day, it remains unsolved. Amazingly, evidence remains today of the bomb blast at 23 Wall Street.