taken about 1:30 in the morning the day isabel was reported missing. the video is from outside a nightclub. detectives want to ask if the men saw anything unusual. the five people are considered potential witnesses, not suspects. investigators are also searching for any video from a baseball game isabel's family attended the night before she went missing. authorities say the parents are fully cooperating with investigators but are not ruling them out as suspects. because of tucson's short distance from the mexican border u.s. marshall as are circulating a picture of the first grader in mexico and working with authorities there who are are checking hotels, bus terminals and other businesses. tonight at 1030 teem there is a benefit concert for isabel called voices of hope and will be held in scottsdale. police are hoping a new $50,000 reward will lead to new information. >> shannon: we certainly will as well.