While this is incredibly embarrassing for Sony, as it exposes gross incompetence, can someone explain why the FBI/law enforcement is not able to shutdown the ha

While this is incredibly embarrassing for Sony, as it exposes gross incompetence, can someone explain why the FBI/law enforcement is not able to shutdown the hackers by filing criminal charges against the owners/operators of lulzsecurity.com, since they are openly admitting that they are behind all of the attacks.