International human rights organisations have asked the Equatorial Guinea government to immediately release two men who head the country’s leading human rights organisation.

The groups - Human Rights Watch, EG Justice, Publish What You Pay, Transparency International, the UNCAC Coalition, Amnesty International, and the International Anti-Corruption Conference - issued a statement Friday to petition the release of Enrique Asumu and Alfredo Okenve.

The two men who head the Centre for Development Studies and Initiatives were detained by police on April 17.

The rights groups noted that the activists had exceeded the 72-hour period that Equatorial Guinean laws permit to detain a person without charge.

“The authorities have a long history of harassing, arbitrarily detaining and generally interfering with the work of human rights defenders in Equatorial Guinea,” Tutu Alicante, the executive director of EG Justice which monitors human rights abuses in Equatorial Guinea notes in the statement.

Mr Alicante is further quoted: “This latest incident shows the authorities’ willingness to trample on the country’s due process of law to intimidate and silence dissent.”

International opinion varies over Equatorial Guinea's governance record ever since the country joined the Portuguese bloc.

The head of the Portuguese NGOs platform for development Pedro Krupenski, last year said the country remained the leading violator of all human rights.

In 2015, before the country formalised joining the Portuguese speaking bloc, Amnesty International said Equatorial Guinea authorities had killed nine opposition members.

President Teodoro Obiang Nguema who has been in power since 1979, has been criticised for persecuting his opponents.

President Nguema won the April 2016 elections with 98 per cent of the votes, making him Africa's longest-serving leader.

He has ruled the former Spanish colony since 1979 when he ousted his uncle in a military coup.

Equatorial Guinea applied to join the Portuguese-speaking Lusophone bloc of countries in 2006.

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