Pakistan's Geo News has sued the Inter-Services Intelligence (ISI) for defamation after accusations of being anti-state, the channel said Friday.
The channel, which is part of the privately-owned Jang Group, has also given ISI 14 days to issue a public apology, Dawn online reported.
Geo News' suit was followed by a suspension of the channel's licence by the Pakistan Electronic Media Regulatory Authority for 15 days along with a fine of Pakistani Rs.10 million (nearly $101,500).
"Geo and Jang Group (have) served a legal notice on the Ministry of Defence, Inter-Services Intelligence and Pakistan Electronic Media Regulatory Authority for defaming and maligning the group," the channel was quoted as saying in a report published in a newspaper owned by the media house.
"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," it said.
In the lawsuit, the channel has now asked the ISI to retract what it called its defamatory statements, publicly apologise and pay $500 million in damages.
The defence ministry in April demanded that the licence of Geo News be suspended after it provided air space to journalist Amir Mir who accused the ISI of being behind the shooting of his brother Hamid Mir, one of Pakistan's most popular television anchors, the report said.
According to the lawsuit, since the dispute began, the channel has been taken off the air in several parts of the country or been moved to obscure slots on the channel lineup by the cable operators, allegedly under pressure from the military.
Distribution of the parent group's newspapers has also been disrupted, it said in the lawsuit.
The channel last month apologised for the allegations in an attempt to resolve the issue.