Physically, the crows are unchanged. t-Virus-infected crows have been known to vary in behaviour. The crows found in the Arklay Laboratory and its associated estate were rather reserved, standing still as humans walked past. Of these crows, they generally only attacked when disturbed by loud noises such as gunfire. Running in the cemetery was also enough to provoke an attack. In the Umbrella Executive Training Center not too far away from the laborarory, a flock of crows attacked Rebecca Chambers and Billy Coen by smashing-through the windows of a room to reach them.