But military prosecutors do not plan to seek the death penalty if Manning is convicted and instead the 23-year-old soldier would face possible life in prison, the army said in a statement.
“The new charges more accurately reflect the broad scope of the crimes” that Manning is accused of committing, said Captain John Haberland, spokesman for the military district of Washington.
The US military had already announced 12 charges against Manning in July, accusing him of violating federal criminal and military law.
The Pentagon has yet to explicitly link him to the WikiLeaks website but suspicion has focused on Manning, who worked as a low-ranking army intelligence analyst in Iraq and reportedly boasted of communicating with the website.
US and Western officials have condemned WikiLeaks for publishing hundreds of thousands of sensitive military documents and diplomatic cables over the past several months.
The charges, following a seven-month investigation, included “wrongfully causing intelligence to be published on the Internet knowing that it will be accessed by the enemy,” theft of public records, transmitting defense information, fraud related to computers, the army statement said.
The WikiLeaks website has yet to disclose its source for the massive trove of secret documents, but suspicion has focused on Manning, who worked as a low-ranking army intelligence analyst in Iraq.
A trial date has yet to be set for Manning and the army said Wednesday that proceedings have been delayed since July 12, 2010 pending the outcome of an inquiry into the soldier’s “mental capacity” requested by defense lawyers, the army statement said.
Manning’s supporters and lawyers have complained about the conditions of his solitary confinement, saying the “maximum security” regime is inhumane and unnecessary.