(Adds details on suspect, sourcing, charges, background) LOS ANGELES, March 4 (Reuters) - A Southern California man whom prosecutors say sought to travel to Syria last year in a bid to join Islamic State fighters was indicted on federal charges, the Justice Department said on Wednesday. The suspect, Adam Dandach, 21, of Orange, California, was indicted by a grand jury in Santa Ana, California, the department said in a statement.