Wark was in command of the 32nd Battalion which crossed the start line at 9am moving south of Bellicourt. When the advance was held up by two machine guns he employed a passing tank to deal with them. He then gathered together 200 leaderless Americans and attached them to his own command. With the support of tanks his men swept through Nauroy at 11.30am taking forty prisoners. When he observed a battery of 77 mm guns firing on his rear companies and causing heavy casualties, Wark collected a few men and rushed the battery, capturing four guns and ten of the crew. With only two non-commissioned officers he pushed forward and surprised and captured fifty Germans near Magny-la-Fosse. At about 3pm Wark halted his troops near Joncourt.

At 7am next day the unit attacked again and advanced 1500 metres to a point just north of Etricourt. Another attack took place at 6am on 1 October and the troops pushed through Joncourt and beyond. Wark’s gallantry was often exhibited as he again led from the front. Regardless of personal risk he dashed forward and silenced machine guns which were causing heavy casualties. This and other successes enabled the division to complete its task of forcing through to the Beaurevoir line.