Harrison immediately ordered the U.S. Secretary of War Stephen B. Elkins to address the situation under Article IV, Section 4, Clause 2 of the U.S. Constitution, which allows for the use of U.S. forces under the President's orders for "protection from invasion and domestic violence". The Sixth Cavalry from Fort McKinney near Buffalo was ordered to proceed to the TA ranch at once and take the WSGA expedition into custody. The 6th Cavalry left Fort McKinney a few hours later at 2 am on April 13 and reached the TA ranch at 6:45 a.m. as the settlers were about to use the Ark of Safety. Colonel J.J. Van Horn, the officer in charge of the unit, negotiated with Sheriff Angus to lift the siege, and in return the Invaders were to be handed to civilian authorities. The Sixth Cavalry took possession of Wolcott and 45 other men with 45 rifles, 41 revolvers and some 5,000 rounds of ammunition, before escorting them first to Fort McKinney and then to Cheyenne.