(Sherwood, OR)  --  A man is behind bars, after being accused of assaulting a Sherwood police officer who responded to a report of a dog locked in a car.  Authorities say the dog's owner, 54-year-old Jeffrey D. Hagg, confronted the officer in the parking lot of a Safeway store on Roy Rogers Road yesterday afternoon.  Officials say the officer was pushed and hit in the head as he and other officers tried to take Hagg into custody.  Hagg is facing charges of assaulting a public safety officer, disorderly conduct, and harassment.