sentences:  On June 24, 1970, two of the I-beams supporting the staging area on the Kittery side of the span gave way, plunging four workers to their deaths and leaving another seven injured.A memorial plaque was placed beneath the bridge on the Maine side, visible from Maine Route 103.The bridge was officially opened on November 1, 1972, in a ceremony attended by the Governor of New Hampshire, Walter R. Peterson Jr., and the Governor of Maine, Kenneth M. Curtis.