Islamabad , Pakistan ( CNN ) -- An anti-drone activist and journalist from Pakistan is missing after being abducted from his home , his lawyer said Monday . Kareem Khan was seized from his home in Rawalpindi on the night of February 5th , according to attorney Shazad Akbar . He was picked up by 20 men , some of them dressed in police uniforms , Akbar said . `` Kareem Khan was my first client in 2010 against U.S. drone strikes in the tribal areas of Pakistan , '' Shahzad told CNN Monday . Shahzad said he lodged a complaint with local police but they denied having picked him up . Khan hails from the tribal area of North Waziristan . He was due to travel to Europe this week to speak to German , Dutch and British parliamentarians about his personal experience with drone strikes , according to Reprieve , a UK-based charity that provides legal support to prisoners unable to pay for it themselves . Khan was also involved in legal proceedings against the Pakistani government concerning its failure to investigate the deaths of his son and brother in a drone strike , the charity said on its website . `` We are very worried about Mr Khan 's safety , '' writes Clare Algar , executive director of Reprieve . `` He is a crucial witness to the dangers of the CIA 's covert drone programme , and has simply sought justice for the death of his son and brother through peaceful , legal routes . '' Khan spoke to CNN in December 2010 about the airstrike a year earlier that had targeted his home in Machikhel , a village in North Waziristan . Khan said the missiles killed his 35-year-old brother , a teacher with a master 's degree in English literature ; his 18 year-old son , and several others . He filed a $ 500 million lawsuit against the U.S. government . Khan was one of the first people to raise awareness about drone strikes , said Noor Behram , a journalist based in North Waziristan . He said it was a great setback that he had disappeared just before he could raise the issue on an international forum during his Europe trip . Behram said a protest against what describes as Khan 's arrest would be held Tuesday at the press club in the town of Miranshah . Muhammad Saleem reported the story from Islamabad , Chandrika Narayan reported and wrote the story from Atlanta .
Pakistani anti-drone campaigner seized from his home , lawyer says . The man was arrested in the city of Lahore on Monday and is being held at a police station for questioning about alleged links to militant groups operating out of Pakistan. Khan was due to travel this week to speak to European parliamentarians .