Pakistani intelligence agents arrested 97 people, including three commanders, who planned a prison break aimed at freeing the killer of US journalist Daniel Pearl.
Army spokesman Lieutenant General Asim Saleem Bajwa said in a conference in Karachi on Friday that three armed groups - al-Qaeda, Lashkar-e-Jhangvi, and the Pakistan Taliban - were working together on the plot to free British-born Ahmed Omar Saeed Sheikh, currently on death row for the 2002 murder of Pearl.
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"A deputy leader of al-Qaeda in the subcontinent named Mussanah was the mastermind of the plan and was arranging all the finances while he was aided by the deputy chief of Lashkar-e-Jhangvi, Naeem Bukhari," Bajwa said.
"These arrests were made over a period of time, starting from the first arrest made a few months ago."
The suspects had been involved in several attacks in the southern port city of Karachi and elsewhere, and planned to kill 35-40 hostages and break about 100 inmates out of a prison, he added.
Talat Masood, a defence and security analyst, told Al Jazeera that freeing "their companions" from jail was only to prove their power.
"The Pakistan army are doing their best to eliminate terrorism, and these arrests are one of their big achievements," he said.
"However, arresting militants and busting their attacks is not the only solution to eradicate terrorism in the country. Pakistan needs to work on cross-border relationships, especially with Afghanistan, which will help them to track terrorists very easily," said Masood.
Pearl was the South Asia bureau chief for The Wall Street Journal when he was abducted and beheaded in Karachi in 2002, while researching a story about armed groups.
A graphic video showing Pearl's decapitation was delivered to the US consulate in the city nearly a month later.
Sheikh was arrested in 2002 and sentenced to death by an antiterrorism court, while three other co-accused received life imprisonment.
In January 2011, a report released by the Pearl Project at Georgetown University in the US following an investigation into his death made chilling revelations when it claimed the wrong men were convicted for Pearl's murder.
The investigation - led by Pearl's friend and former Wall Street Journal colleague Asra Nomani and a Georgetown University professor - claimed that the reporter was murdered by Khalid Sheikh Mohammed, the alleged mastermind behind the September 11, 2001, attacks, not Sheikh.
Mohammed was arrested in Pakistan in 2003 and is being held in Guantanamo Bay.
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Source: Al Jazeera and agencies