ISLAMABAD - Pakistan's ex-military ruler General Pervez Musharraf was formally indicted by a court Tuesday for his alleged role in the 2007 assassination of former premier Benazir Bhutto.
“He 's charged with abetting and conspiracy to murder [Benazir Bhutto]," Musharraf’s lawyer, Ilyas Siddique, said after the court hearing in Rawalpindi. "Abetting means he helped in the murder. Conspiracy means he planned something illegal which led to the murder."
Musharraf, who was once Pakistan’s most powerful man and was its ruler at the time of Bhutto's assassination, denies the charges. "Our position is categorically not guilty," Siddique added.
His indictment is an unprecedented event in a nuclear-armed country ruled by the military for half of its 66-year history, and shatters an unwritten rule that the top military brass are untouchable as the South Asian country tries to shake off the legacy of decades of military rule.
Bhutto was killed in a December 2007 gun and suicide bomb attack after an election rally, weeks after she returned to Pakistan from years in self-imposed exile.
Pakistani Taliban militants were blamed for the attack. However, a 2010 United Nations report said Bhutto's death could have been prevented and said Musharraf's government has “failed profoundly” to give her adequate protection.
However, a former adviser to Musharraf described Tuesday's case as “politically motivated.”
“Saying he failed to provide ample security to Benazir Bhutto is a non-starter,” Chaudhry Faisal said. “Legally, it's not the president's job to provide security."
Faisal, who wrote about the case Tuesday in Pakistan’s Dawn newspaper, added: “If an army chief can be prosecuted for a murder he isn't related to, or a security failure he is not directly involved in, wouldn't they be in the dock tomorrow as well, considering there is a security failure almost every day in this country?"
Five alleged militants were charged in 2011 over the attack, but they have yet to face trial.
Musharraf lost power with the return to democracy in 2008, and spent time in exile before returning to Pakistan.
There was tight security at the court for Musharraf's appearance Tuesday, where Judge Chaudry Habib ur Rehman read out the charges against him, and six others accused.
Another hearing was scheduled in the case for Aug. 27.
NBC News' Alastair Jamieson and Reuters contributed to this report.