From the Human Rights Watch statement "Israel: End Arbitrary Detention of Rights Activist":

Israeli authorities have detained Othman without charge for more than two months on what appear to be politically motivated grounds. On the basis of secret evidence that Othman and his lawyers were not allowed to see, a military court confirmed a military order that consigned Othman to three months administrative detention without charging him with any crime. Othman has no criminal record and, to the knowledge of Human Rights Watch, has never advocated or participated in violence. His detention period, which may be renewed, ends on December 22.

"The only reasonable conclusion is that Othman is being punished for his peaceful advocacy," said Sarah Leah Whitson, Middle East director at Human Rights Watch. "The authorities interrogated him for months, then ordered him held some more, but they won’t say why they are holding him and haven’t accused him of any crime."

Learn more about Othman’s here – http://freemohammadothman.wordpress.com/.