Vanceboro International Bridge Bombing - Bombing

Bombing

Horn left New York from Grand Central Station on a New Haven Railroad passenger train to Boston on January 29, 1915, carrying a suitcase of dynamite. He took the overnight train out of Boston (operated by the Boston and Maine Railroad), placing the suitcase of explosives in a lower berth. Horn's sleeping car was transferred to the Maine Central Railroad in Portland and proceeded east across Maine to the Maine Central's eastern terminus at the border hamlet of Vanceboro the following day. Upon arrival in Vanceboro, Horn checked into the Exchange Hotel and was observed hiding the suitcase of explosives in a wood pile outdoors while scouting out the railway bridge on the border over the St. Croix River several hundred feet to the east; this bridge was jointly owned by the Canadian Pacific Railway and the Maine Central Railroad. At least three Vanceboro residents reported his suspicious behaviour to the U.S. immigration inspector. The inspector interviewed Horn at the hotel and Horn assured him that he was merely a Danish farmer looking to purchase land in the area. Horn spent the next two days maintaining a low profile and watching the extremely busy Canadian Pacific Railway main line in order to determine the schedule of trains.

On the night of Monday, February 1, 1915, Horn checked out of the hotel claiming to be catching a train that evening. He apparently changed into a German army uniform, to avoid being convicted of being a spy and executed, before proceeding to the railway bridge over the St. Croix River sometime after midnight.

Horn proceeded to position a suitcase filled with explosives on the Canadian side of the bridge but was interrupted by an oncoming train and was forced to move out of its path. After he was sure it had passed he proceeded to reposition the explosives. However he was interrupted a second time by another train. Puzzled and not wanting to kill anyone, he waited until 1:07 a.m. on February 2 before again repositioning the bomb on a girder. Horn cut the fuse, this changed the time before the explosion from fifty minutes to only three. Horn lit the fuse with a cigar and somehow made it back to the Exchange Hotel through a gale in −30 °F (−34 °C) temperature before the dynamite exploded. At 1:10 a.m. on Tuesday, February 2, 1915 the bomb exploded, blowing out windows across Vanceboro and St. Croix and exposing residents to the freezing air outside. Some iron beams on the bridge were twisted or bent but the damage was relatively minor.

Horn had frostbite on his hands and was assisted by the proprietor of the hotel who allowed him to check back in for the night. The proprietor connected the explosion with Horn's suspicious presence and, upon being informed by residents of the community who had discovered the source and target of the explosion, informed the CPR who closed the bridge and re-routed trains pending a safety inspection.

Railway officials inspected the bridge the following morning and discovered the damage was relatively minor, resulting in the bridge being out of service for several days.