Richard C. Brown and Herbert J. Bass, One Flag One Land, vol. 1 (Morristown, NJ: Silver Burdett Company, 1986), 465.
Within the northern United States, a number of fights and riots occurred when slave catchers tried to return blacks to their masters. For example, in 1854 in Boston, slave catchers seized Anthony Burns, an escaped slave. It took marines, cavalry and artillery to hold back the thousands of people who tried to keep Burns from being returned to his Southern master. The attempt to free him failed. Nevertheless, a few months after his return to the South, Northern abolitionists purchased Anthony Burns from his master and sent him to Canada.