A spokesman for Springfield Mayor Domenic Sarno says there's no word on whether there have been any fatalities in Friday evening's blast.
A spokeswoman for Baystate Medical Center says eight people are being evaluated in its emergency facilities and none has critical injuries.
The explosion sent bricks and glass flying through downtown streets. Police Sgt. John Delaney says authorities are evacuating the commercial and residential area.
A witness in a barbershop tells WWLP-TV he heard a loud explosion that knocked him across the shop.
He says he looked up the street and saw one building severely damaged. The station reports two buildings have been damaged and the blast was felt miles away.
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