Sumiyoshi was informed by Hyakutake's staff of the postponement of the offensive to 24 October, but was unable to contact his troops to inform them of the delay. Thus, at dusk on 23 October, two battalions of the 4th Infantry Regiment and the nine tanks of the 1st Independent Tank Company launched attacks on the U.S. Marine defenses at the mouth of the Matanikau. U.S. Marine artillery, cannon, and small arms fire repulsed the attacks, destroying all the tanks and killing many of the Japanese soldiers while suffering only light casualties.