Final answer:
The fire at the Old Minnehaha County Jail started due to various reasons. The spread of fire led to the trapping of inmates and resulted in fatalities. The stairwell doors were locked, making it difficult for the inmates to escape.
Step-by-step explanation:
The fire at the Old Minnehaha County Jail started due to various reasons. The fire quickly spread throughout the building, trapping many inmates inside. Some of the inmates were beaten and shot by a vengeful mob, while others tried to escape by breaking windows or jumping out. The stairwell doors were locked, making it difficult for the inmates to find a way out. Additionally, the poorly constructed fire escape collapsed, leading to further fatalities.