Michael Downs, 19, was in a San Fernando court Wednesday morning.
The district attorney added three new victims to the case, bringing the total number to 17. The victims range in age from 12 to 16 years old.
Downs is accused of luring some victims by befriending them on Facebook.
The mother of one of the victims didn't want to be identified, but she said parents need to be careful of Facebook.
"People are portraying themselves as children or adolescents which are adults and are preying on our kids through Facebook. As innocent as you may think it is, it's not at all," she said.
Downs is currently being held on $1.8 million bail. His arraignment is scheduled for Feb. 6.
Nicky Jackson Colaco, a Facebook Safety representative, could not comment about the specific case Wednesday, but released a statement about protecting minors on the site:
"Nothing is more important to us than protecting the many teens that use our service. We've devoted significant resources to developing innovative and complex systems to proactively monitor the site for suspicious activity, and we employ a large team of professional investigators who evaluate any reports of potential abuse surfaced by our systems and by people who use Facebook.
"Facebook also employs robust tools to protect minors from unwanted contact and solicitation. For example, minors can only receive Messages on Facebook from friends or the friends of those friends, and never by strangers. Additionally, when a minor who is new to our service receives a friend request, we might interpose a message along the lines of 'Only accept friend requests from people you really know' before the minor can confirm that he or she wants to accept the friend request. We use innovative technical mechanisms to flag suspicious adult behavior. For instance, if an adult sends an unusual number of friend requests to minors that are ignored or rejected, our warning systems might be triggered, which initiates a Facebook inquiry so that remedial action can be taken, if necessary.
"Our privacy and visibility settings take into account the unique needs of people between the ages of 13 and 17, and are more restrictive than the settings for adults in nearly all cases. For example, a minor's sharing is automatically restricted to no more the minor's friends and friends of those friends, or their networks, which are typically associated with their schools. Minors never have listings created for them in search engines off of Facebook, and the ability to share their location is automatically defaulted to 'off.' Unlike adults, minors can only be 'tagged' on Facebook by their friends or the friends of those friends. Facebook's 'Tag Review' feature, which is a privacy option that allows people to approve or reject tags that others add to their posts, is automatically turned 'on' for minors."