The 5th marched with Taylor from Fort Texas to Point Isabel in late April to clear their supply route of Mexican troops. While they were fortifying that base, the Mexican Army of the North laid siege to Fort Texas, beginning a bombardment of the post on 3 May. Taylor's army marched back from Point Isabel and met the enemy on 8 May, at Palo Alto, several miles east of the fort. In the resulting battle, the 5th Infantry broke a charge by Mexican lancers trying to break through to Taylor's supply train. Over night, the Mexicans withdrew to a better defensive position at Resaca de la Palma, which Taylor's army assaulted on the morning of the 9th. After stiff initial fighting, U.S. dragoons overran the Mexican artillery. The 5th and 8th Regiments then led a charge that broke the Mexican center and routed their army.