A lawyer for the founder of the WikiLeaks website says a secret grand jury is meeting outside Washington to consider charges in the release of thousands of sensitive U.S. documents.
The lawyer, Mark Stephens, told David Frost on Al-Jazeera television that they have heard from Swedish authorities that there has been a "secretly empaneled" grand jury in Alexandria, Virginia.
Since late last month, WikiLeaks has been slowly releasing some 250,000 U.S. diplomatic cables. It previously released thousands of U.S. military documents on the wars in Afghanistan and Iraq.
U.S. Attorney General Eric Holder says he has authorized significant steps to be taken in response to the latest leak. He did not elaborate.
The founder of WikiLeaks, Julian Assange, is currently being held by British authorities while he fights extradition to Sweden, where he is wanted for questioning about allegations of rape, sexual molestation and unlawful coercion. Assange denies any wrongdoing.