Three people were killed and four were seriously injured Wednesday when a bridge in Mississippi that was closed nearly a month ago collapsed while a work crew was prepping it for demolition, authorities said. The bridge over the Strong River on State Route 149 in Simpson County, about 40 miles south of Jackson, had been closed to traffic since Sept. 18 as part of a bridge replacement project, the Mississippi Department of Transportation said in a news release.

Gov. Tate Reeves said in a post on social media late Wednesday that first responders from the county and "other state assets have been on the scene at the tragedy" where they'd confirmed at least three fatalities, the reports. The local sheriff says four people were critically injured.

US Transportation Secretary Pete Buttigieg said in a social media post late Wednesday that the Federal Highway Administration was "engaging state officials concerning" the "premature collapse during demolition of a bridge on State Route 149 in Mississippi." Terry Tutor, the Simpson County coroner, told the that seven men were working on the bridge, using heavy machinery to tear it down, when it gave way and plummeted nearly 40 feet. The DoT said one of its inspectors was at the work site when the bridge collapsed, and that person was unharmed.

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