Farouk Abu-Issu, the head of the opposition National Consensus Forces party, has been admitted to a police hospital in Sudan's capital Khartoum.

81-year-old Farouk was arrested 6 December by security forces upon his return to Khartoum from Addis Ababa, where he signed the "Sudan Appeal" with other armed and unarmed opposition leaders.

"This is the first time we have seen him since he was arrested, and we are very worried about his health," his daughter Nahla Abu Issa told Reuters news agency by phone.

Nahla said her father suffers from diabetes, high blood pressure, and heart problems.

Besides Farouk, the security agents arrested two other "Sudan Appeal" signatories, Sudan Human Rights Monitor President Amin Mekki Madeni and Farah Agar.

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