FACTBOX: CIA used waterboarding on 9/11 suspect

(Reuters) - The Pentagon on Monday sought murder and conspiracy charges against the alleged planner of the September 11 attacks, Khalid Sheikh Mohammed, and five others.

Mohammed was subjected to the simulated drowning technique known as waterboarding during CIA interrogations.

Following are several facts about the controversial tactic, which human rights advocates condemn as torture:

* U.S. President George W. Bush authorized the CIA to use waterboarding during interrogations of senior al Qaeda suspects after the September 11 attacks but insists the United States does not torture.

* CIA Director Michael Hayden told Congress that waterboarding was used against Mohammed and two others -- senior al Qaeda members Abu Zubaydah and Abd al-Rahim al-Nashiri; Hayden also told lawmakers he is not certain the technique would be legal under current U.S. law.

* According to Human Rights Watch, waterboarding dates at least back to the Spanish Inquisition. In some versions, the group says prisoners are strapped to a board, their faces covered with cloth or cellophane, and water is poured over their mouths to simulate drowning. In other versions, prisoners are dunked headfirst into water.

* The technique causes reflexive choking, gagging and the feeling of suffocation.

* Waterboarding was used in Central and South America in the 1970s and 1980s, the rights organization says.

* The U.S. government has launched an investigation into the CIA's destruction of interrogation videotapes that are believed to depict waterboarding along with other harsh questioning techniques.

(Reporting by David Morgan in Washington; editing by David Wiessler)