WORCESTER, Mass. (WCVB) —An explosive fire left 17 people homeless in Worcester Saturday, while firefighters escaped serious injury after a backdraft blew out a window on the fourth floor of the Lafayette Street building, showering glass and debris 30 feet away. As firefighters were climbing a stairway to the fourth floor, a backdraft explosion blew out windows on the upper floor, Deputy Fire Chief Geoffrey Gardell told The Telegram.