On December 23, advance units of the British fleet reached the Mississippi River. Lafitte realized that the American line of defense was so short as to potentially allow the British to encircle the American troops. He suggested that the line be extended to a nearby swamp, and Jackson ordered it done. The British began advancing upon the American lines on December 28, but were repulsed by an artillery crew manned by two of Lafitte's former lieutenants, Renato Beluche and Dominique Youx.