A collision with an elk caused some traffic problems on I-5 northbound last night near Woodland. State Troopers say that the incident happened around 11:30 pm, at milepost 24 between Woodland and Kalama. At least one elk was hit by a northbound vehicle as several animals tried to cross the highway. Lanes were blocked for about an hour as the injured animal and the damaged vehicle were removed. No human injuries were reported.