A fifth Pakistani social media activist has gone missing since last week

© AFP/File ADEM ALTAN

Islamabad (AFP) - A fifth Pakistani rights activist has gone missing, his colleagues said Thursday, as the United Nations raised concerns over shrinking freedoms for campaigners.

Samar Abbas, a middle-aged IT worker and head of the anti-militancy Civil Progressive Alliance, disappeared under mysterious circumstances after arriving in the capital Islamabad from the southern port city of Karachi on Saturday, January 7, according to Talib Raza, a colleague from his organisation.

"We formed the alliance to protect the rights of minorities. He had launched a struggle against the banned militant outfits' activities and we together staged protests for the rights of the minorities," said Raza.

"This seems to be an organised attempt to shut the progressive and liberal voices in the country," he added.

Four leftist bloggers were previously reported missing from various cities in Pakistan between January 4 and 7, raising fears of a crackdown on social media, the last bastion of free speech in a country where journalism is increasingly under threat.

Human Rights Watch said their near simultaneous disappearances raised concerns of government involvement.

The government has denied this, and on Tuesday Interior Minister Chaudhry Nisar Ali Khan told the Senate authorities would soon recover all the missing.

Rights groups say Pakistani activists and journalists often find themselves caught between the security establishment and militant groups including the Taliban.

The United Nations and Amnesty International have expressed concern for the missing activists.

"No government should tolerate attacks on its citizens," said the UN's special rapporteur on the right to freedom of expression, David Kaye.

"By making the investigation of these disappearances an urgent priority, the Pakistani authorities can send a strong signal that they take seriously the responsibility for the life and security of all of its citizens, particularly in cases involving freedom of expression."

Pakistan is also ranked among the world's most dangerous countries for journalists, and reporting critical of the military is considered a major red flag, with journalists at times detained, beaten and even killed.

In April 2014, unidentified gunmen attacked but failed to kill Hamid Mir, one of the country's most recognised TV anchors. His employer and his family later accused the director general of the powerful Inter-Services Intelligence agency of involvement.

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