General Halleck suspected escaped slaves of spying for the South, and ordered that they not be allowed in camp in Missouri.
From the New York Times:
ST. LOUIS, Thursday, Nov. 21.
Gen. HALLECK has issued orders that, in consequence of important information respecting the number and condition of our forces being conveyed to the enemy by fugitive slaves, no such persons shall be hereafter permitted to enter the lines of any camp, nor any forces on the march, and any now within such lines to be immediately excluded therefrom.
The General also call the particular attention of all officers commanding posts or troops in the field, to the importance of preventing unauthorized persons of every description from entering or leaving our lines and of observing the greatest precaution of employment of agents and clerks in confidental positions.
The General also directs all Staff Officers of this Department, whose Staff duties have ceased under the recent special order from Washington, but who still hold commissions in the regular army, or volunteers mustered into the service of the United States, to immediately report in person, if in St. Louis, or by letter, if elsewhere, to these headquarters.
The latest accounts from Gen. PRICE place him in Barry County, making preparations to advance to Springfield.