(Oregon City, OR) -- The U.S. Coast Guard is searching for a tug boat that went missing in the Willamette River. The 25-foot tug boat sank on December 13th when helping a barge near the I-205 bridge. Two people who were on board were able to get off the tug boat before it became submerged. Officials say the strong river current is an obstacle in trying to get the boat out of the river.