Petersburg from a small force of Confederate defenders at the Second Battle of Petersburg, also known as Grant's first offensive at Petersburg. By June 18, the Army of Northern Virginia reinforced the Confederate defenders, ending the possibility of a quick Union victory. At the start of the campaign, the Union forces could pin down most of the Army of Northern Virginia to their trenches and fortifications running from northeast of Richmond to southwest of Petersburg but was not strong or large enough to surround the Confederate Army or to cut all supply routes to Petersburg and Richmond or to turn the Confederate Army out of its defenses. The smaller Confederate Army was strong enough to maintain their defenses and to detach some units for independent operations but not large enough to send a field army out to fight a major battle with the Union force that might compel a retreat. Grant's strategy Grant's strategy was to destroy or cut off sources of supply and sever supply lines to Petersburg and Richmond, which also would result in extending to the breaking point the defensive lines of the outnumbered and declining Confederate force. In pursuit of these objectives, Grant launched five more offensives at Petersburg during the remaining months of 1864, another in February 1865, and two more at the end of March and beginning of April 1865. During the fall of 1864 and the winter of 1864–1865, Grant slowly extended the Union Army line south of Petersburg westward. Lee extended the Confederate line to match the Union moves, but the defenders were stretched increasingly thin. Battle of Hatcher's Run On February 5, 1865, Grant sent a large force of cavalry and the V Corps of infantry toward Dinwiddie Court House and Stony Creek Station to interrupt the Confederate's Boydton Plank Road supply route and capture large numbers of wagons with supplies reported to be en route. The raid on the supply route and supplies accomplished little as only 18 wagons were found on the road A significant result of the offensive was the extension of the Union line to the west from Fort Sampson to the Vaughan Road crossing of Hatcher's Run and captured two key road crossings of Hatcher's Run near Armstrong's Mill. The action of the II Corps, which was promptly joined by the V Corps, in moving to protect the attacking force and to defend their advanced positions,