File No. 812.00/16001.
The Secretary of State to the Confidential Agent of the Constitutionalist Government.
Washington, October 6, 1915.
Sir: Referring to your letter of September 1, 1915, in regard to a statement that American soldiers have been firing across the Rio Grande at Mexicans, the Department informs you that it is advised by the War Department that the commanding officer of the Southern Department and troops along the Mexican border reports as follows:
The firing complained of occurred at Progreso. An unlicensed ferry had been operated at the point and when marauding bands begun crossing the river into American territory a detachment of the 12th Cavalry was stationed there and ordered to prevent all crossing. In order to carry out their orders it was necessary to establish a patrol in the vicinity. This patrol was fired on by armed parties from the Mexican side on three successive days. Our patrols had to return the fire in order to prevent the detachment from being driven away from the crossing. The third attack was participated in by about 70 armed men, some of them evidently Carranza soldiers since 2 of the latter were wounded there. It was in repelling this attack that one soldier was killed and one officer and 3 soldiers were wounded.
Detachments of soldiers engaged in the performance of their prescribed duty of patrolling have been fired on at several other places along the river and in the city of Brownsville itself. In some cases the fire was not returned but in most cases it was returned because that was the only way by which the detachments could continue to carry out their orders.
In not a single case, however, have our detachments been the aggressors. They have returned the fire only in self-defense and firing has been stopped as soon as the object was accomplished.
All United States troops on border duty were instructed, in order to avoid the danger of drawing fire from the Mexican side, to locate their camps out of sight from the Mexican side and to avoid exposing themselves to view any more than was absolutely necessary to properly perform their duties.
General Nafarrate, the Mexican commander in Matamoros, has been requested on several occasions to cooperate with military authorities on the American side of the border, with a view to preventing the attacks on United States troops. He promised to do so but so far has failed to accomplish anything.
I am [etc.]