The spring of 2004 was particularly bloody in Ramadi. In the opening days of the rebellion that began in April 2004, and which was dominated by the siege of Fallujah, 2/4 suffered one of the deadliest attacks of the war, losing 12 Marines in a single day, April 6, 2004. During this time, with most of the 1st Marine Division's resources focused on Fallujah, 2nd Battalion 4th Marines (2/4) and 3rd Battalion 11th Marines (3/11) were left with the burden of controlling Ramadi.