Blogger Aasim Saeed, who went missing in January 2017, has applied for asylum in Britain after alleging that he was tortured during his captivity.
He was one of the five social media activists who vanished from different cities of Pakistan earlier this year before being released.
Third missing activist found, flees country fearing for life: family
Prior to his abduction, Saeed told the BBC, he had been involved in running a Facebook page critical of the establishment, called Mochi.
He was working in Singapore but had arrived in Pakistan for his brother's wedding in January when he says a few men in plain clothes arrived at his house and ordered him into a car.
"'Do you know why you've been picked up?' they asked. I said, 'I have no idea'. Then he started to slap me. They said, 'Let's talk about Mochi'."
Saeed told the BBC he was asked to hand over the passwords to his email accounts and mobile phone before being taken to a secret detention facility where he was held alongside men he believed to be "religious terrorists".
According to the BBC, the Human Rights Commission of Pakistan (HRCP) had put the number of people forcibly "disappeared" in 2016 to 728. Authorities in Pakistan, however, have often said the security services are unfairly blamed for the disappearances and that the number of missing people is inflated, it added.
The blogger also alleges that he was beaten with a leather strap. "I don't remember what happened, I fell down and someone was holding my neck in his feet, and the other guy kept beating and beating and beating." Saeed describes his arms and back being left "shades of purple, blue and back".
At another detention facility, Saeed says he was made to undergo polygraph tests while being questioned about links to the Indian intelligence service, the Research and Analysis Wing (RAW).
"Have you ever been associated with RAW? Who is your handler? Have you ever received money from RAW?" He denies links to any foreign intelligence services and says the interrogators analysed his Facebook posts.
HRCP to raise a shriller voice for other missing bloggers
Saeed returned home after several weeks in detention. He told the BBC it was only then that he realised he had been accused of blasphemy.
The blogger returned to Singapore shortly after being released and arrived in the UK in September to visit friends.
He told the BBC he had then decided to apply for asylum as the terms of his employment visa in Singapore meant he had no guarantee he would be allowed to keep living there if he ever lost his job, and his life would be in danger if he returned to Pakistan.
This story originally appeared on the BBC.
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