On Friday night, residents milled around the neighborhood where the explosion occurred, stunned by the destruction and confused by the cordoned-off area, which grew as crews continued to search for gas leaks. The mayor warned against looting, saying police would be out in force.
Wayne Davis, who lives about a block away from the destroyed building, said he felt his apartment shake.
"I was laying down in bed, and I started feeling the building shaking and creaking," he said.
The Navy veteran said the boom from the explosion was louder than anything he'd ever heard, including the sound of a jet landing on an aircraft carrier.
The blast was so loud it was heard in several neighboring communities. Video from WWLP-TV showed the moment of the explosion, with smoke billowing into the air above the neighborhood.
Associated Press writers Rodrique Ngowi, Bridget Murphy and Bob Salsberg in Boston and Jessica Hill in Springfield contributed to this report.
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