ACCRA, Ghana — Ghana's main opposition party said on Sunday the country's presidential election had been manipulated, hours after local media reported its candidate Akufo-Addo had narrowly lost to incumbent John Dramani Mahama.

"The results are flawed. We are not satisfied," said Yaw Buaben Asamoa, a spokesman for Akufo-Addo's National Patriotic Party. "There has been manipulation on many levels," he told Reuters by phone, adding that his movement would hold a press conference soon to give more details.

Ghana's election commission has not yet issued official results, but widely-read news website Joy News compiled tallies from polling stations and projected Mahama would win the election in the first round with slightly over 50 percent of the votes.