On June 28, 1863, Confederate Gen. J.E.B. Stuart left Rockville with three cavalry brigades, 125 captured Union supply wagons, and more than 400 military and civilian prisoners, arriving in Brookeville that night. Prisoners Maj. James C. Duane, chief engineer of the Army of the Potomac, and Capt. Nathaniel Michler of the U.S. Army Corps of Engineers repeatedly urged Stuart to parole them, and after he finally consented, paroles prepared at Brookeville and at Cooksville the next morning slowed his advance. The prisoners were not fed, and only white men were permitted to stop for water as they crossed streams; Confederates slashed at blacks if they attempted to drink and shot one who was too weak to continue. Most civilian prisoners walked home from Brookeville. Thomas Bailey and Mortimer Moulden, Rockville's postmaster and provost marshal, refused parole because they feared Eblen, a recuperating young Union soldier, would be shot if he could not keep the pace. They were marched to Cooksville and released on the night of June 29, then helped Eblen back to Rockville, sometimes carrying him, in a journey of 70 miles. While Stuart paroled prisoners, Gen. Fitzhugh Lee took his brigade north to the Baltimore and Ohio Railroad at Hood's Mill, where just after dawn on June 29, 1863, his cavalrymen tore up track, destroyed the bridge at Sykesville, and cut the telegraph line, severing one means of communication between the Army of the Potomac and Washington.