(Bloomberg) -- A blast at a fireworks company outside of Moscow injured at least 56 people at the site of a plant controlled by the Rostec industrial and defense holding known for making optical-electronic equipment used by the military.Most Read from BloombergEveryone Wants to Work at UPS After Teamsters DealFirst American City to Tame Inflation Owes Its Success to Affordable HousingTycoon Who Gave Away $750 Million Sees Profit in Loans to PoorWeWork Tumbles After Raising ‘Substantial Doubt’ Ab