President Wilson remarked of the incident that it was "a regrettable incident at a private railroad terminal", and Edgar E. Clark of the Interstate Commerce Commission was dispatched to investigate. Soon after the explosion, suspicion fell upon Michael Kristoff, a Slovak immigrant. Kristoff would later serve in the United States Army in World War I, but admitted to working for German agents (transporting suitcases) in 1915 and 1916 while the US was still neutral. According to Kristoff, two of the guards at Black Tom were German agents. It is likely that the bombing involved some of the techniques developed by German agents working for Ambassador Count Johann Heinrich von Bernstorff, who covertly acted as a spymaster while under German Foreign Office cover, and Captain Franz von Rintelen of the intelligence wing of the German Imperial Navy, using the cigar bombs developed by Dr. . von Rintelen used many resources at his disposal, including a large amount of money. von Rintelen used these resources to make generous cash bribes, one of which was notably given to Michael Kristoff in exchange for access to the pier. Suspicion at the time fell solely upon suspected German intelligence operatives Kurt Jahnke and Lothar Witzke, who are still judged as legally responsible. It is also believed that Michael Kristoff was responsible for planting and initiating the incendiary devices that led to the explosions. Additional investigations by the Directorate of Naval Intelligence also found links to some members of the Irish republican Clan na Gael organization and far-left organizations. Irish socialist and labour union leader James Larkin asserted that he had not participated in sabotage, but admitted to having encouraged work stoppages and strike actions in munitions factories, in an affidavit to McCloy in 1934. The United States did not have an established national intelligence service, other than diplomats and few military and naval attaches, making the investigation difficult. Without a formal intelligence service on the national level, the United States only had rudimentary communications security and no federal laws forbidding espionage or sabotage except during wartime, making the connections to the saboteurs and accomplices almost impossible to track. Aftermath This attack was one of many during the German sabotage campaign against the neutral United States, and it is notable for its contribution to the shift of public opinion against Germany, which eventually resulted in American support to enter World War I. The Russian government sued