While the Second Battle of Deep Bottom was going on, Grant had sent troops south of Petersburg to capture the Weldon Railroad. This was another of Grant's simultaneous operations. The Weldon Railroad was the only connection between Petersburg and the last Atlantic seaport at Wilmington, North Carolina. Grant had failed to capture the Weldon Railroad in June. The Union V Corps under General Gouverneur K. Warren was ordered to move west, destroy the tracks and, if possible, hold the rail line. Warren was successful in destroying tracks. But attacks and counterattacks went on for the next three days. The action cost the Union Army 4,279 casualties and the Confederates lost between 1,600 and 2,300 dead, wounded or missing. The Union was able to extend its lines west and built a fort named after Union General James S. Wadsworth, who was mortally wounded at the Battle of the Wilderness.