(Portland, OR) -- Police need witnesses and video from an incident June 14th on I-5 north of the Failing Street pedestrian bridge. A man in the freeway threw construction cones and boards with nails sticking out onto the freeway. He also had a large stop sign on a portable stand. Officers found an improvised explosive device and closed the freeway. The freeway was closed for an hour before 38-year-old Alexander Wick was taken into custody. Police need witnesses, especially those with video, to contact detectives.