Robert Rios with Victory Outreach Ceasefire checks certain sites daily. His job is to get kids out of gangs like Sureño and Norteño. As gang members turn to websites like MySpace, Twitter, and YouTube to get their messages out, he follows them.
"So if we know something, that kids get on there and they start talking, 'Tomorrow we're meeting at so and so park, tomorrow we're going to be at this school, we're going to do this, we're going to do that,' we try to send teams out to that neighborhood and be there to intercept," explained Rios.
Outreach groups are not the only ones monitoring these social media sites.
Law enforcement agencies in Southern California do too. But police in the South Bay would not comment, saying only that they do not discuss which investigative tools they do or do not use.
"They're looking at your MySpace, they're writing every single thing you're doing," said former Sureño gang member Ivan Padilla. "They're keeping an eye on you and you don't even know it. Things you say, they're using it against you."
In the past Padilla used MySpace to intimidate people through photos and suggestive lyrics like, "You best watch out who I am, you got to respect and bow down to my Sureño."
Now that he is out of a gang, his MySpace page is very different.
Norteño gang member Christian Jacquez was released from prison two weeks ago. He knows several people who were arrested for parole violations which were tracked through MySpace.
"A lot of them are in there for showing their pictures with guns," he said.
Some websites are cooperating with police and handing over account user information, but only with a search warrant.