The order changes little for Mr. Musharraf in immediate terms. Mr. Musharraf, a retired army general, is already under house arrest at his villa on the edge of Islamabad, the Pakistani capital, in a case involving his detention and firing of senior judges after imposing emergency rule in 2007.
Mr. Musharraf was brought to the Rawalpindi court under tight security on Friday. He was ordered to return on Tuesday, said Salman Safdar, one of his lawyers.
The prosecution’s case rests on a statement by Mark Siegel, a Washington lobbyist and friend of Ms. Bhutto’s, who alleges that Mr. Musharraf made a threatening phone call to her before she returned to Pakistan in 2007 from self-imposed exile, Mr. Safdar said.
Prosecutors will question Mr. Musharraf about Mr. Siegel’s statement, as well as about allegations that he sent a threatening e-mail to Ms. Bhutto and failed to provide security to Ms. Bhutto, Zulfiqar Ali, special prosecutor for the Federal Investigation Agency, which is spearheading the investigation, was quoted as saying in local news media.
Mr. Musharraf, 69, himself returned to Pakistan last month after four years in exile, hoping to carve out a place in politics. But his plans quickly went awry. His party received little public support, and the national election commission disqualified him from running in the general election, scheduled for May 11.
And he found himself in court. In all, Mr. Musharraf faces charges in four different cases — all related to decisions made during his nine years in power — as well as possible treason charges. Last week he tried to avoid arrest in the judicial firings case by dramatically fleeing an Islamabad court, protected by bodyguards, before eventually surrendering to the police.
A decision on whether to file treason charges, which carry a potential death penalty, will probably be made by the next government.
Mr. Musharraf’s supporters and lawyers say all the cases are politically motivated.
“I would call this a political case, based on mala fide,” Mr. Safdar said in an interview about the Bhutto case on Friday evening, using the Latin for “bad faith.” “This is a prosecution merely on the basis of suspicion. The prosecution does not have concrete, tangible evidence.”
Mr. Safdar said that Mr. Musharraf had not been implicated in Ms. Bhutto’s assassination until 2010, a year after he left Pakistan, and that Interpol had declined to arrest him despite four requests by the government that succeeded him.
Mr. Musharraf took to power in 1999 after a bloodless coup and wielded immense power until 2007, when his rule began to crumble. A botched attempt at removing Chief Justice Iftikhar Muhammad Chaudhry set off a political opposition movement that he failed to contain.
Ms. Bhutto had left the country in 1998 to avoid corruption charges stemming from her time as prime minister in the 1990s, and had become a leading opposition figure in the meantime.
Mr. Musharraf grudgingly allowed Ms. Bhutto to return, but they quickly developed differences. He briefly put her under house arrest after her return in October 2007, and on Dec. 27, after addressing a political rally in Rawalpindi, Ms. Bhutto was assassinated in a gun and bomb attack.
Mr. Musharraf’s government blamed Baitullah Mehsud, the former leader of the Pakistani Taliban, for masterminding the attack. Ms. Bhutto’s supporters have long insinuated that Mr. Musharraf’s military-led government also played a role.
Seven Pakistani men, including two police officers, are currently on trial in the assassination case. The police officers are accused of failing to provide adequate security for Ms. Bhutto and of removing crucial evidence at the behest of Mr. Musharraf.
Mr. Musharraf insists that Ms. Bhutto died because of an “internal security breach,” said Mr. Safdar, the lawyer.
One of Pakistan’s most charismatic, popular and polarizing politicians, Ms. Bhutto had become a larger-than-life figure, despite accusations of corruption and mismanagement during her two terms in power in the late 1980s and early 1990s.
A public wave of sympathy after her assassination catapulted her Pakistan People’s Party to power in the 2008 elections. Her husband, Asif Ali Zardari, was elected president later that year after Mr. Musharraf resigned under the threat of impeachment. The Zardari-led party headed a coalition government that completed its five-year term last month.
The images of Ms. Bhutto’s assassination remain a powerful symbol for her party, which has used them in its election campaign to win voter support.
Mr. Musharraf remains in high spirits and determined to prove innocence, Mr. Safdar said. “Mr. Musharraf has two expectations — fair investigation and justice.”
A version of this article appeared in print on April 27, 2013, on page A6 of the New York edition with the headline: Pakistan: New Charges Filed Against Musharraf in Bhutto Case.