 At that point, the Marines had only managed to gain control of about 25 percent of the city.During the fighting in Anbar there was also a major insurgent attack on the city of Ramadi on April 6, 2004, which began when a force of 300 insurgents attacked Marine patrols throughout the city in an attempt to relieve pressure on Fallujah.In heavy street fighting over four days 16 U.S. Marines and an estimated 250 insurgents were killed.