Four left-wing activists have gone missing over the past seven days in Pakistan, according to relatives and human rights organisations.
Ahmed Raza Naseer became the latest to disappear on Saturday, while authorities have launched an investigation into the potential kidnapping of renowned rights activist Salman Haider in Islamabad on Friday.
Two other men, Waqas Goraya and Asim Saeed, disappeared on 4 January, reports the Daily Pakistan.
Zeeshan Haider told NBC News his brother never came home after going out with friends on Friday evening.
Mr Haider’s wife then received a text message from her husband’s phone telling her to collect his car from a motorway, according to the brother.
It remains unclear who is responsible for the alleged kidnappings, but a spokesman for the Interior Ministry in Pakistan told NBC the government was “going to do everything it can to locate Mr Haider”.
All four activists are united by their vocal criticism of Pakistan’s security establishment and conservative groups.
Mr Raza is thought to be been behind an anti-conservative Twitter account, which was removed from the social media platform by 8 January.
Mr Haider, Mr Goraya and Mr Saeed all used Facebook to post liberal views to their followers.
On 10 January, students and supporters held a demonstration for the missing bloggers.
Jamila Gillani, former leader of Awami National Party, a secular left-leaning party in Pakistan, said law enforcement agencies did not “have the right to take away political, social, human rights activists and writers”.
“In the light of the constitution of the country the citizens have the right to assembly, freedom of speech, thoughts and opinion,” she added.
Since the disappearance of Mr Haider, the hashtag #RecoverSalmanHaider has been trending on Pakistani social media.
Pakistan is routinely rated one of the most dangerous countries in the world for journalists to work in.
Reporters Without Borders ranked the country 147th out of 180 countries in 2016 for levels of freedom available to journalists.
Extremist groups, Islamist organisations and Pakistan’s intelligence agencies have all been linked to assaults on press freedom.
