By 2004, she was the only woman on the FBI’s most wanted list of al-Qaeda terrorists. But her real notoriety came in 2008, when police in Afghanistan arrested her carrying plans for a “mass casualty attack” on targets in New York, including the Empire State Building and the Statue of Liberty. The plans allegedly referred to chemical and biological weapons, complete with likely casualty rates for different methods of attack.

Even so, when a detachment of FBI and special forces soldiers were dispatched to pick Siddiqui up, they underestimated the threat she posed. When one soldier sat down, laying his assault rifle by his foot, she grabbed it and opened fire, shouting “Get the f— out of here!” While no soldiers were hit, Siddiqui was shot in the stomach in the ensuing melee and nearly died before being transferred to the US for trial. She was convicted in 2010 of trying to murder American soldiers.

After she was sentenced, Ayman al Zawahari, al-Qaeda’s then number two, called on Muslims to “avenge” her imprisonment. But it is not just Islamist radicals who have questioned her detention. In Pakistan, which has long been a reluctant partner in America’s war on terror, rumours have spread widely. Some relatives insist that Siddiqui and her children were abducted for several years by US intelligence, spending time at a prison at Bagram Airbase in Afghanistan. They also allege that the children, who were returned to family custody after Siddiqui’s arrest, were not actually hers.

That may sound unlikely. But to many in Pakistan, so too is the idea that a slightly-built woman like Siddiqui could grab a rifle from a highly-trained US special forces operative and come close to killing them.

Public demonstrations have been held in her name, and even Imran Khan, the cricketer-turned-politician who is now Pakistan’s prime minister, has backed her cause.

Her case has also been regularly cited in hostage negotiations involving Islamic militant groups, although officials suspect that in some of them, this may simply be because she is one of the few female prisoners the kidnappers have heard of.

Lawyers for Siddiqui have said that she played no part in inciting this weekend’s hostage incident at the synagogue. 

Some Muslim community groups have backed Siddiqui’s cause. In a statement last year, a branch of the Council on American-Islamic Relations in Austin, Texas, said she had been “kidnapped, ripped apart from her children, shot at, renditioned to the US and is currently serving an 86-year prison sentence for a crime she did not commit”.

Mindful of the support her case has among Pakistan’s religious Right, Mr Khan has even offered a prisoner swap for Siddiqui himself. In 2019, he offered to release Shakeel Afridi, a Pakistani surgeon who helped the CIA track down Osama bin Laden to his hideout in Abbottabad, Pakistan, in 2011. A year later Pakistan sentenced Afridi to 33 years in jail for “colluding with terrorists”, in what some believe was revenge for his work with US authorities.  

Few, though, believe such an exchange is likely any time soon, given Washington’s fear that Siddiqui might get a heroine’s welcome back in Pakistan.

As things stand, she is not due for release until 2082 – if, indeed, she survives that long. Last July, she suffered serious burns after another inmate smashed a coffee mug filled with boiling water into her face, according to a recent legal suit filed by her lawyers.  

For her supporters, such attacks on Prisoner 90279-054 will only fuel the sense of injustice – and possibly also further attacks in her name.