Updated:LAWRENCE, Mass. (MyFoxBoston.com) -- An overnight incident an industrial building triggered a hazardous materials team to respond and sent some firefighters to the hospital.
Lawrence firefighters responded to the scene at around 1:30 a.m. Sunday at a metal company on Ballard Way. When fire crews went inside, they found a broken container full of nitric acid in the back of the building that had reacted with another chemical, creating nitric gas.
Four firefighters were sent to the hospital to be treated for minor injuries. All have since been released.No one else was hurt, but multiple homes nearby were evacuated after a vapor cloud formed above the building. Residents were let back into their homes at around 9:30 a.m. Sunday.
Officials are now trying to figure out exactly what happened.
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