Activists in Equatorial Guinea alleged on Monday that plainclothes security forces snatched and beat up the head of their human rights and development organisation at the weekend.Alfredo Okenve was "sequestered... (and) mistreated by security forces wearing civilian clothes", the Centre for Studies and Initiatives for the Development of Equatorial Guinea (CEID-GE) said in a statement.A relative of Okenve's, Analeto Medja, told AFP: "He was taking his brother to the airport. Four people stopped his car and forced him at gunpoint to get into theirs. They took him to some wasteland and beat him hard until he was bleeding, then they left him there."Residents close to the scene took Okenve to a hospital in Bata, Equatorial Guinea's economic capital on Africa's Atlantic seaboard, Medja and other family members said.The oil-rich country's political capital is Malabo on the island of Bioko, lying off the coast of Cameroon to the northwest of the mainland and its dense tropical forests.The identity of the men in civilian clothes who attacked Okenve was unclear on Monday, but carrying firearms is tightly controlled by the iron-fisted regime of President Teodoro Obiang Nguema Mbasogo, in power since 1979.The affair was being followed widely on social networks on Monday, but there was no official reaction.CEID-GE said it would file a formal complaint, denouncing the harassment of civil society in the former Spanish colony.Okenve was arrested and detained for several days in April 2017 for celebrating the 20th anniversary of the CEID-GE. He was released after a bail payment of $3 500.Human rights groups have repeatedly denounced Obiang Nguema, 76, for his repression of political opposition, independent civil society organisations and the media.In February 2018, the European Union expressed concern at the "serious deterioration in the human rights situation" in Equatorial Guinea, which is also known for the lavish spending of Obiang's son and vice president, Teodorin Nguema Obiang.A French court in October 2017 gave Teodorin Obiang a suspended fine of $34m and a suspended three-year jail term after convicting him of looting public funds from his country to pay for a rich playboy's lifestyle in Paris.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.