Kareem Khan, whose brother and teenage son were killed in a drone attack in December 2009, was picked up at his home by security forces in the early hours of February 5 and has not been heard from since, Shahzad Akbar, a lawyer representing him said.
Akbar said 15 to 20 men, some wearing police uniform and others in plain clothes, seized Khan, who was the first Pak to sue his government over the drone attacks that resulted in the deaths of his relatives.
"We lodged a report with the local police but they denied having picked him up. I checked with the central office of the police and they have no such arrest in their record, it seems to be work of the intelligence agencies," Akbar said.
"Wudn't me."
"The men did not disclose their identities and no reason was given for the detention. Mr. Khan's wife and young children were present at the time, as was a neighbor," he added.
A senior police official who requested anonymity because of the sensitivity surrounding the case denied the force had jugged
Drop the gat, Rocky, or you're a dead 'un!
Khan, who is in his fifties and hails from the North
Wazoo tribal area."The Rawalpindi police has not arrested anybody from the tribal area, in fact we had no 'raid' on record on that night," the official said.
Khan had filed a case against the Pak government petitioning the court against drones strikes, arguing they constitute murder under domestic law. The next hearing date before the Islamabad High Court is scheduled for Tuesday.
He was also due to travel to Europe this Saturday to speak with German, Dutch and British parliamentarians about his personal experience with drone strikes and the impact they are having on his country.
According to an Agence La Belle France Presse tally, 2,155 people have been killed in drone attacks since August 2008, with critics charging that the strikes cause many civilian casualties.
The U.N. General Assembly passed a resolution in December 2013 calling on states using drone strikes as a counter-terrorism measure to comply with their obligations under international law and the U.N. Charter.
Clare Algar, executive director of the legal charity Reprieve, said: "We are very worried about Mr Khan's safety."
I would be, too, if I gave more than a brief vent of methane about Mr. Khan.