BROCKTON, Mass. (AP) – Brockton residents marked the 100th anniversary on Sunday of a deadly boiler explosion and fire at a shoe factory that killed more than 50 people and burned an entire city block.

On March 20, 1905, workers were greeting one another when the steam boiler at R.B. Grover & Co. ripped through the four-story, wooden building. The blast ignited a gas-fueled fire that quickly roared into an inferno that raced through the building and beyond.

The blast and fire killed 56 people that day, and more died two days later from their injuries. About 150 people were injured.

The explosion destroyed the Dahlborg block at Calmar and Main streets, a tavern building next to it, and set seven houses on a nearby streets ablaze.

“It was the worst disaster in the city’s history,” Gerry Beals, chief curator at the Brockton Historical Society, told The Enterprise of Brockton.

The fire was so fierce that rescue operations were stopped and teary police officers had to hold back friends and relatives from rushing into the burning structure to save their loved ones.

A relief fund raised thousands of dollars to aid victims and their families, and a monument was erected at Melrose Cemetery with the names of those who perished and the remains of unidentified victims buried beneath.

R.B. Grover was founder and owner of the company, which was known for its moderately priced, comfortable Emerson shoe, named after Charles O. Emerson, the company’s chief financial officer. The factory, built around 1891, employed 400 workers. The factory never reopened.

A committee was formed to determine who would be compensated and how much they would receive.

Assistance was divided into those who were injured, widows and other adult dependents of those who were killed, and orphaned children.