They graded the flat prairie and had reached Five-Mile Creek (about 3 miles from the fort) when word reached Mullan and Colonel George Wright (commander of Fort Dalles) that Brevet Lieutenant Colonel Edward Steptoe had been routed by a group composed primarily of Cayuse, Schitsu'umsh, Spokan, and Yakama warriors at the Battle of Pine Creek (near present-day Rosalia, Washington) on May 17, 1858.