Two years after the start of World War I, the greater New York region was a major hub of the American munitions industry, with “75 percent of all ammunition and armaments shipped from the United States to Europe went out within a radius of five miles of City Hall in Lower Manhattan,” according to “Sabotage at Black Tom” by Jules Witcover. It was Black Tom, once a small island, that was “the single most important assembly and shipping center in America for munitions and gunpowder being sent to the Allies,” Witcover notes, and “probably housed the most extensive arsenal anywhere outside the war zone itself.”

Black Tom explosion. (Credit: Bettmann / Getty Images)

While the United States had not yet entered World War I and was officially neutral, American munitions dealers could legally sell to any of the warring nations. Most of the arms, however, were going to the Allies—Britain, France and Russia—because the British navy had blockaded Germany.

The first of the Black Tom explosions was felt at 2:08 a.m. followed half an hour later by a second blast. At least five people were killed, including a baby in Jersey City who was thrown from his crib, and there was an estimated $20 million—the equivalent of some $500 million today—in property damage.

Store windows broken in Black Tom Explosion. (Credit: Bettmann / Getty Images)

The blasts also wreaked havoc at the site. As described by Witcover: “The Black Tom promontory was a charred ruin; 13 huge warehouses were leveled and six piers destroyed, and fires continued to eat their way through the remains and consume hundreds of railroads cars and barges tied to the docks. At one point, a huge cavern was hewed out of the earth by the explosions of some 87 dynamite-laden railroad cars. The blast excavated a hole so deep that it extended below sea level; water seeped in until a vast pond was created, strewn with the wreckage.”

Wrecked warehouses and scattered debris attest to power of an explosion. (Credit: US Army Signal Corps / Getty Images)

In the aftermath of the explosions, law-enforcement agents quickly arrested officials from the railroad, storage company and barge business who operated from the Black Tom site. However, investigators were unable to determine whether the disaster was the result of safety violations by any of these officials. One thing the authorities initially seemed to agree on was that the explosions weren’t the work of foreign saboteurs. It would take years for a persistent team of American lawyers to find sufficient evidence that showed that in fact the disaster had been plotted by the Germans. The lawyers sued Germany in the Mixed Claims Commission at The Hague, and in 1939 won the case. Germany, under the rule of Hitler, failed to pay up and the settlement was renegotiated in the early 1950s. The last payment was made to Black Tom claimants in 1979.

Fire raging at National Storage House, one of plants blown up by the explosion and spreading of fire. (Credit: Bettmann /Getty Images)

Today, the Black Tom site is part of New Jersey’s Liberty State Park. Nearby at the Statue of Liberty, a legacy of the disaster remains: Due to the damage the statue sustained on July 30, 1916, its torch has been closed to the public for the last century.