A California man who appeared in al-Qaeda propaganda videos has been charged with treason by a US court.
Mr Gadahn is thought to have appeared in many al-Qaeda videos
Adam Gadahn, 28, has become the first US citizen to be charged with treason since World War II, officials said.
Mr Gadahn, who is also known as Azzam al-Amriki or Azzam the American, is believed to be a fugitive in Pakistan.
Previously known as Adam Pearlman, he converted to Islam as a teenager and most recently appeared in a video with al-Qaeda ideologue, Ayman al-Zawahiri.
In the video released last month, he exhorted his fellow Americans to convert to Islam and said US soldiers fighting in the Iraqi and Afghan conflicts should switch sides.
No Muslim, he said, should "shed tears" for Westerners killed in terrorist attacks.
The indictment against Mr Gadahn said he had "knowingly adhered to an enemy of the United States... with intent to betray the United States".
A deputy US attorney described the treason charge as "exceptionally severe".
The charge carries penalties ranging from a five-year prison term to death.
Mr Gadahn grew up on a goat farm near Los Angeles.