WASHINGTON: A US soldier accused of leaking military video footage from Iraq and suspected in the release of thousands of classified documents about the war in Afghanistan has been transferred to a US military jail, the US Defense Department said on Friday.

Private First Class Bradley E. Manning arrived at Quantico Marine Base in Virginia on Thursday night, the Pentagon said, after his court martial proceedings were transferred from Camp Arifjan, Kuwait.

Manning is facing four charges related to the leak to whistleblowing website WikiLeaks of a video showing a US Apache helicopter strike in Baghdad in July 2007 that killed several people.

He now is also suspected of involvement in the leak to the same website of thousands of pages of classified documents related to the war in Afghanistan.

The video of the helicopter attack was posted the Internet by WikiLeaks in April this year. It prompted an international outcry and renewed demands for compensation from the victims` families.

In addition to leaking the video, Manning, 22, is accused of illegally downloading more than 150,000 diplomatic cables, 50 of which he is alleged to have transmitted unlawfully to the danger of US national security.

The Wall Street Journal reported Thursday that authorities have evidence linking Manning to the latest secret US material released by WikiLeaks -- 92,000 classified US military files on the Afghan war between 2004 to 2009.

The release sparked condemnation from the Pentagon, White House and Afghan President Hamid Karzai, and fears that Afghan informants named in some of the documents could now be at risk.

The Pentagon said a criminal investigation into Manning`s actions remains open.

In a statement, the Defense Department said his transfer to the United States had been requested "due to a potentially lengthy pre-trial confinement because of the complexity of charges and an ongoing investigation."

BDST: 2039 HRS, July 30, 2010