Islamabad, Pakistan - Three of five Pakistani activists who disappeared three weeks ago have been released and are safe, their family members say, although it remains unclear who abducted them.

The family of Asim Saeed, a Singapore-based IT manager who was abducted from his home in the eastern city of Lahore on January 4, told Al Jazeera on Sunday that he had been released.

Saeed has now left the country, the Reuters news agency reported, citing his father.

The families of Ahmed Raza Naseer, a shopkeeper from the town of Nankana Sahib, and Salman Haider, a noted progressive activist, poet and university lecturer, told Al Jazeera their relatives had also been released on Saturday.

The whereabouts of two other activists - Waqas Goraya and Samar Abbas - who also disappeared in early January - remain unknown. All five men went missing from across Punjab province and the capital Islamabad within four days of each other in early January.

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The disappearances prompted a series of protests by rights groups across Pakistan, calling for the government to locate the men, or for them to be produced in a court to face formal charges if they had been detained by the state's intelligence agencies.

No one, including state agencies, has taken responsibility for detaining the men, but Ghulam Haider, Saeed’s father, said his son had been taken by an unnamed intelligence agency.

"It was no one other than the state agencies who took him," Haider told Reuters.

He said Saeed was picked up because of a social media post intelligence agencies deemed "objectionable".

"My son is not against any agency, he is not against the military or government and he is not against Islam," Haider said. "The fact that he was set free means that he has been cleared of all charges."

Haider was referring to a slew of blasphemy allegations that were levelled against the five activists on social media and some mainstream television news channels in the days following their abduction.

Blasphemy can carry a judicial death sentence in Pakistan, and, increasingly, right-wing vigilantes have murdered those accused in acts of targeted violence. At least 68 people have been killed in violence related to blasphemy allegations since 1990, according to an Al Jazeera tally.

On January 19, a rally calling for the release of the activists in the southern city of Karachi was attacked by stone-throwing right-wing protesters.

Families of all five activists have denied the blasphemy allegations, and repeatedly stated their fear that their relatives could be attacked, even after their release.

"Always now […] he will be looking over his shoulder all the time," Zeeshan Haider, Salman’s brother, told Al Jazeera earlier. "It is a permanent threat."

Other families have reported receiving death threats via telephone calls since the allegations surfaced.

Pakistan’s government has long been accused by rights groups of carrying out a campaign of disappearances, with thousands said to be in custody, and some allegedly killed while detained.

The Pakistani government denies any wrongdoing in the case of the five missing activists.

"The only instruction Asim got from the agencies was that he could not give any media interviews," Saeed’s father said.

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