An unknown powder in envelops found at a Danbury business prompted a brief HAZMAT response yesterday. A vendor at the Shops at Marcus Dairy on Sugar Hollow Road reported finding 6 envelopes shortly after 11:30am. The incident was deemed a police matter, though the fire department also responded and said the issue was resolved by around noon. There were no evacuations. Officials believe the substance does not appear to have been anything serious. No further details were available.