 The 2nd Infantry Division , however , did not know the strength of the roadblock on the night of November 29 . At the same time , the US 25th Infantry Division Military Police mistakenly reported that the alternative retreat route from Kunu @-@ ri to Anju was also blocked by Chinese . Later , Coulter ordered Keiser to withdraw by breaking the roadblock with the 27th Commonwealth Brigade . On the early morning of November 30 , Keiser made the decision to withdraw through the valley . 
