The controlled-burn fires were started Friday in an effort to make it easier to move the derailed train cars after the fires were extinguished Saturday, the Canadian Broadcasting Corp. reported.
CN spokesman Jim Feeny said crews have removed the derailed cars from scene and work has begun to repair the damaged track.
Nine of the train's 122 cars derailed near Plaster Rock Tuesday. The train was carrying oil.
"Investigators found a cracked wheel on a car near the front of the train. This wheel moved on the axle and lost track gauge, resulting in the derailment of that wheel set. There was also a broken rail," investigators reported.
Local officials met with nearby residents at about 11 a.m. Saturday to update them on the situation.
Evacuees, except those who live within a 330 feet safety zone have been allowed to return to their homes.