▁dispers ed ▁in ▁August ▁ 1 9 3 3 , ▁Song ▁Z he y uan ▁made ▁him ▁Ba och ang ▁g arrison ▁commander ▁in ▁Ch ah ar . ▁ ▁In ▁September ▁ 1 9 3 3 , ▁ ▁he ▁assist ed ▁Fu ▁Zu oy i ▁against ▁some ▁of ▁his ▁former ▁com r ades , ▁purs uing ▁and ▁blocking ▁them ▁east ▁of ▁Er ta izi , ▁S ui y uan ▁when ▁they ▁attempted ▁to ▁move ▁west ▁to ▁N ing x ia ▁via ▁S ui y uan , ▁forcing ▁them ▁east ▁to ▁join ▁F ang ▁Z hen w u ▁at ▁D ush ik ou . ▁ ▁By ▁the ▁out break ▁of ▁war ▁with ▁Japan , ▁Z hang ▁was ▁with ▁the ▁ 3 7 th ▁Division ▁and ▁served ▁in ▁the ▁early ▁campaign s ▁of ▁the ▁Second ▁S ino - J apan ese ▁War ▁in ▁North ▁China . ▁ ▁In ▁August ▁ 1 9 3 7 ▁Z hang ▁had ▁become ▁commander ▁of ▁the ▁ 3 7 th ▁Division ▁succeed ing ▁F eng ▁Ch ian . ▁Under ▁his ▁command ▁ 3 7 th ▁Division ▁fought ▁in ▁the ▁Be ip ing – H ank ou ▁Railway ▁Operation ▁from ▁August ▁ 1 9 3 7 ▁to ▁Mid ▁August ▁ 1 9 3 7 ▁under ▁ 7 7 th ▁Corps ▁of ▁ 1 st ▁Army ▁Group . ▁His ▁Division ▁was ▁involved ▁in ▁the ▁T ian jin – P uk ou ▁Railway ▁Operation ▁for ▁a ▁short ▁time ▁in ▁September ▁and ▁then ▁returned ▁to ▁fighting ▁in ▁the ▁other ▁operation ▁until ▁January ▁ 1