Islamabad, Pakistan (CNN) -- Hundreds of thousands protested in Karachi and Hyderabad Tuesday against the 86-year prison sentence for a Pakistani scientist convicted of attempting to kill Americans in Afghanistan.
The rallies were organized by the Muttahida Quami Movement, a Pakistani political party, in response to last week's sentencing of Aafia Siddiqui, who was convicted by a jury in February in the United States on seven charges, including attempted murder and armed assault on U.S. officers.
"I appeal to the U.S. government and their people to release Aafia Siddiqui with honor and dignity to get the praises of millions of people," MQM's leader, Altaf Hussain, said during a live address by telephone from his self-exile in London, England.
Hussain also questioned "why the people who are responsible for the drone strikes in Pakistan and killing innocent people" are not given similar sentences.
The United States does not officially comment on suspected drone strikes. But it is the only country in the region known to have the ability to launch missiles from drones -- which are controlled remotely.
Siddiqui's sentence -- which the country's foreign minister called "very harsh" -- has sparked widespread protests.
"Many people feel that she is innocent and she was framed and she should have got a fairer chance," Pakistani Foreign Minister Makhdoom Shah Mahmood Qureshi said last week of the demonstrations.
Prosecutors said Siddiqui picked up a rifle and shot at two FBI special agents, a U.S. Army warrant officer, an Army captain and military interpreters while she was being held unrestrained at an Afghan facility on July 18, 2008.
The agents returned fire, shooting her in the abdomen.
Siddiqui was extradited to the United States in August 2008, after the shooting incident.
At her sentencing last week, the 38-year-old MIT graduate shook her head in defiance and wagged her finger in a "no" gesture as U.S. District Judge Richard M. Berman laid out the case against her.
But Siddiqui was more subdued when Berman allowed her to speak before the packed courtroom filled with family, spectators and foreign and national press.
Clad in a khaki suit and a hijab that covered most of her face, Siddiqui repeatedly asked her Muslim supporters to not "get emotional."
"I don't want any violence in my name," Siddiqui said of the demonstrations in Pakistan, where her case has become a cause celebre. "If you do anything for me, please educate people about Islam because people don't understand that it is a religion of mercy."
CNN's Nasir Habib contributed to this report.