On January 25, 1787, over 1,000 Regulators led by Captain Daniel Shays and other leaders marched on the United States Arsenal at Springfield, Massachusetts. Approximately 1,200 government militia under General William Shepard of nearby Westfield defended the Arsenal. In this letter written to Governor James Bowdoin the following day, General Shepard reports that the Regulators continued to advance despite repeated warnings. Shepard therefore ordered his men to fire the Arsenal artillery into the ranks of the approaching Regulators, killing four men. Although the Regulators fled without firing a shot, General Shepard tells the Governor he is convinced that he and his men must "expect to be attacked this day by their whole force combined."