Democratic Republic of Congo's new President Felix Tshisekedi fell ill as he was delivering his inauguration speech on Thursday following the country's first peaceful handover of power.
State television interrupted its live broadcast of the historic event after Tshisekedi said "I don't feel well" and halted the speech.
He takes over from Joseph Kabila, who led the country since 2001.
Questions remain about the disputed December 30 vote, but Congolese largely have accepted Tshisekedi's win in the interest of peace.
The 55-year-old Tshisekedi, son of the late opposition icon Etienne, was inaugurated at the Peoples' Palace, the seat of the national legislature in the capital, Kinshasa.
Supporters who for decades backed the elder Tshisekedi's pursuit of power streamed into the venue with Congolese flags tucked into their hair or wearing leopard-print caps and cravats. Some fainted in the heat.
Just one African head of state, Kenya's President Uhuru Kenyatta, was seen at the ceremony after the African Union and the international community expressed reservations over alleged election fraud that brought Tshisekedi to power. The United States and others this week have said they will work with the new leader but did not offer congratulations.
Tshisekedi’s election was endorsed by the country’s court after a challenge by another opposition leader. The US yesterday endorsed him as president.
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