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 .
Thus , at dusk on 23 October , two battalions of the 4th Infantry Regiment and the nine tanks of the 1st Independent Tank Company attacked on the U.S. Marine defenses at the mouth of the Matanikau .