In mid-March 1864 Union forces actively probed the Texas coastline. On March 17, a Federal force landed near Corpus Christi seeking contraband cotton; the Federals soon evacuated, taking seized cotton and Texas Unionists with them.
At Laredo, 200 Union troops harassed that city before retiring; Confederate Colonel Santos Benevides requested urgently needed supplies and reinforcements, fearing that the Union raid had exposed how short of manpower he was. On Monday, March 21, a Union warship fired on the Matagorda, a Confederate blockade runner, which had run aground near Velasco.
Confederate shore batteries managed to explode an artillery shell above the Union warship, driving her crew below deck and forcing the warship to withdraw. The Matagorda would be saved, only to be destroyed in July 1864 while running out of Galveston, Texas.