Longstreet had his men firmly entrenched along Marye's Heights. On December 13, under Burnside's orders, troops from the Union Right Grand Division under Sumner launched fourteen frontal assaults against Longstreet's troops, who unexpectedly found themselves at the center of the battle. When Lee expressed apprehension that the Federal troops might overrun Longstreet's men, Longstreet replied that as long as he had sufficient ammunition he would "kill them all" before any of them reached his line. He advised him to look towards Jackson's more tenuous position to the right. Longstreet was proven correct, for from their strong position, Longstreet's men easily held off all of the Union assaults, while Jackson managed with greater difficulty to repel a much stronger Union attack led by the division of George Meade. One Union general compared the scene before Marye's Heights to "a great slaughter pen" and said that his men "might as well have tried to take Hell".