Friends of a missing college student are turning to social media in search of help in finding their friend.
Brett Olson, 20, was last seen Sunday on Beer Can Beach after tubing down the Sacramento River in Butte and Glenn Counties.
A friend launched a Facebook page called "Let's Bring Brett Home", and by Thursday morning it had more than 50,000 members.
Friends are tweeting celebrities, asking them to spread the word about Brett's disappearance. Thursday morning, Olympic gold medal beach volleyball player Kerri Walsh had posted the information on Facebook and Twitter.
One friend posted a photo of Brett showing him at the same beach in 2011. In the photo, he is wearing the same swim trunks he was wearing when he was last seen.
Friends are also using social media to coordinate search activities in the Chico area, as well as his hometown of Lafayette, California in the Bay Area.
Brett's parents tell KRCR Newschannel 7 it's very unusual for him to be out of contact.
The "Let's Bring Brett Home" facebook page can be found at this link: