Gwoemul (pronounced "gae - mul"), aka by its international(and American) title "The Host", is a 2006 Korean sci-fi film featuring a huge, reptilian monster that appears out of a river and terrorizes a local community. A family, losing one of their own to the creature's attacks, take it upon themselves to find and kill the mutant monster when local authorities drag their proverbial asses handling the crisis.
The CGI used to render the huge monster is stellar and the first(and primary) creature rampage is actually a daylight attack on the locals. I own the Region 3 DVD of this 2006 Korean monster movie. A sequel to The Host is in the works. Check out a trailer for this movie by clicking on the video below: