In 1960 immigrants were forced to work in unsafe working conditions, they barely made enough to support their families, and they live in fear of deportation. On March 17, 1960, five Italian immigrant workers, Pasquale Allegrezza, Giovanni Battista Carriglio, Giovanni Fusillo, Alessandro and Guido Mantella, climbed 35 feet underground to continue their work on a tunnel at Hogg’s Hollow, under the Don River near Old York Mills Road and Yonge Street in Toronto. The tunnel was only 6 feet wide. The men had to crawl under a 36-inch water main. They hadn’t been equipped with hard hats or flashlights.
When a fire broke out, they were trapped, unable to see their way out, blocked anyway by smouldering cables on one side and a cement tunnel support wall on the other. Panicked rescue workers shut down air to the tunnel, causing a cave-in, and as compression was lost, the men suffered the torture of nitrogen bubbling up in their bloodstream. The floor wasn't properly sealed so when the water was poured onto the fire the floor collapsed causing a mudslide that buried the men alive.