Ousman Sonko, a former interior minister of Gambia suspected of human rights abuses, will have to remain in Swiss detention, the Swiss Federal Tribunal has ruled.

Switzerland’s highest court has rejected an appeal by Sonko's lawyers against a second prolongation of his detention.

+Why the Sonko case could be tried in Switzerland

The Federal Tribunal said in a decision published on FridayExternal link that Sonko was still under urgent suspicion. As in a previous judgement on an appeal by Sonko, judges said they based their decision on independent reports by United Nations special observers on Gambia. These observers had not yet been questioned by the Office of the Attorney General (OAG) and the OAG also needed to go through files obtained from Gambia during the mutual assistance procedure, the latest judgement said.

It added that the severity of the criminal charges and the international nature of the case meant that a lengthy procedure could be expected.

In the meantime, a separate court has prolonged Sonko’s detention a third time until January 25, 2018.

Sonko, who sought asylum in Switzerland last year was arrested in January. He allegedly commanded a special squad known for its brutality against citizens in the west African state of Gambia.

Trial International, an international justice organisation, accused Sonko of having personally taken part in what it described as torture between 2006 and 2016. Sonko served under ousted Gambian leader Yahya Jammeh.

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