 The American crossing had been seen by a local militia captain , who rushed to the British camp at Trois @-@ Rivières and reported to General Fraser . Thompson left 250 men to guard the landing and headed the rest towards Trois @-@ Rivières . Unfamiliar with the local terrain , he convinced Antoine Gautier , a local farmer , to guide the men to Trois @-@ Rivières . Gautier proceeded , apparently intentionally , to lead the American army into a swampy morass from which it took them hours to extricate themselves . In the meantime , the British , having been alerted to the American presence , proceeded to land troops from the fleet and formed battle lines on the road outside the village . Ships were also sent up to Pointe du Lac , where they drove the American guards there to flee across the river with most of the boats . 
