>> within 24 hours of finding joshan's body, investigators went to hansen's trailer to question him, but he was gone. >> we talked to the park manager and some of the neighbors and they said they hadn't seen him in a day or two. >> a background check revealed hansen, a day laborer, estranged from his wife, had no history of violence. >> a 60-year-old man, having teens hang around his house does lead to suspicion as to what is going on. >> while police searched for hansen, criminalists measured for tire impressions found near joshan's body. those measurements and tread patterns were entered into a computer database that showed 20 different tires manufactured around the world. >> there were then several different manufacture models that could have made that tire impression at the crime scene. different manufacturers sometimes sell their mold to