Pakistani television channel Geo News is suing the powerful spy agency for defamation over accusations of being anti-state, it said on Friday, in a move unprecedented in a country where public criticism of the military is taboo.
In the latest twist in a saga that has captivated the country, Pakistan's media regulator also suspended Geo for 15 days for reporting that the ISI spy agency was behind the April shooting of one of Pakistan's most famous journalists.
"Geo and Jang Group (have) served legal notice on the Ministry of Defence, Inter-Services Intelligence (ISI) and Pakistan Electronic Media Regulatory Authority (PEMRA) for defaming and maligning the group," the channel said in a report published in a newspaper owned by its parent company.
"More than 8,000 journalists, workers and professionals attached to the group and their families are not only being harassed but also attacked and tortured across Pakistan."
Geo News has also given the ISI 14 days to retract its accusations and issue a public apology.
The standoff over Geo, part of the privately owned Jang Group, has exposed divisions between Prime Minister Nawaz Sharif and the army which has ruled the country for more than half of its history.
The military has long seen the government's resistance to efforts to shut Geo News as a sign of defiance and PEMRA's latest move is seen as a compromise solution after weeks of tension.
In April, Pakistan's Defence Ministry had demanded that the licence of Geo News be suspended after it reported that the ISI was behind the shooting of one of Pakistan's most famous journalists.
The PEMRA media regulator said in a statement on Friday it had formally shut down Geo News for 15 days and imposed a $101,500 fine.
"The authority...took a strong notice of violations committed by Geo News and unanimously decided to immediately suspend the licence of the said channel for a period of 15 days besides imposing a fine of Rs10 million," the regulator announced in a statement.
But even before the PEMRA order, the channel had been taken off the air in several parts of the country since the dispute began, allegedly under army pressure, according to its lawsuit.
Distribution of the parent group's newspapers has also been disrupted.
Last month, the channel apologised for the allegations against the ISI but temperatures have failed to cool.
A spokesman for the military was not immediately available for comment.
April's shooting of Hamid Mir, a journalist anchoring Pakistan's top political news talk show, sent a chill through the media community weeks after television anchor Raza Rumi was attacked in the city of Lahore. Rumi survived but his driver was shot dead.
Although Pakistani media have become increasingly vibrant in recent years, with stories exposing corruption or injustices appearing frequently on the pages of the country's many dailies, public criticism of the army or the ISI is largely taboo.
No one has claimed responsibility for the recent assaults, although the Taliban, holed up in mountains on the Afghan border, have made repeated threats against domestic and foreign reporters for portraying the insurgency in a negative light.