 On 26 January , a combined U.S. Army and Marine unit called the Composite Army @-@ Marine ( CAM ) Division advancing westward encountered the Yano Battalion at the <unk> River . Yano 's troops temporarily halted the CAM 's advance and then slowly withdrew westward over the next three days . On 29 January , the Yano retreated across the <unk> River , where soldiers from the 2nd Division had constructed another defensive position . 
