 When Prentiss learned that Peabody had sent out a patrol without his authorization he was outraged and accused the Colonel of provoking a major engagement in violation of Grant's orders, but he soon realized he was facing an assault by an entire Confederate army and rushed to prepare his men for defense.By 9 a.m. Union forces at Pittsburg Landing were either engaged or moving toward the front line.Both Peabody and Powell were soon killed in the subsequent fighting.