On this day in Duluth in 1965, a bomb exploded causing heavy damage to a house trailer used as the temporary headquarters of the Ryan Construction Company of Janesville, Wisconsin. The explosion occurred at 2:40 when the building was empty, and no one was injured—and it was the fifth bomb incident involving the company. The bombings were part of a jurisdictional labor dispute between Duluth’s Local 25 chapter of the International Union of Operating Engineers (IUOE) and Local 49, the chapter employees of the Ryan firm belonged to. The state highway department had awarded Ryan a contract for dredging work on a project involving Highway 53 between Duluth’s High Bridge and 22nd Avenue West, and Local 25 felt it had jurisdiction over Local 49. On June 21 a bomb exploded on a cabin cruiser owned by Frank Galeski, who owned a gas station that supplied fuel to Ryan Construction. On July 11, the Janesville home of Thomas Ryan, company vice president, was firebombed. On July 20 a bomb damaged a truck driven by a Ryan employee on Rice’s Point. And on July 23 in Coon Rapids, a stick of dynamite destroyed a window of the home of Dale Burchett, business manager of Local 49. The Duluth Herald offered a $100 reward after the fourth blast and doubled the offer after the fifth. Duluth mayor George D. Johnson demanded the IUOE put an end to the dispute, saying, “Duluth is a peaceful city and we will keep it that way at all costs.” Whether the mayor’s words mattered to the Union employees is unknown, but the bombings stopped even though the dispute continued.