Opposition leader Buhari wins elections in Nigeria

The results of Nigeria's weekend elections showed that the country's incumbent president Goodluck Jonathan was defeated by his opposition leader, the former military ruler Muhammadu Buhari.

Amid warnings from the UK and US of political meddling during the collation process, the results were made public on Tuesday evening.

Read more: US and UK warn of political interference in Nigeria's election

However, the counting of votes was interrupted by a senior official of the ruling party, who made accusations of "bias and tribalism" against the president of the Electoral Commission.

At least 15 people were shot dead during polling, most of them in the north-east of the country, where Islamist group Boko Haram is very powerful, Reuters reported.

It is the first time in Nigeria's history that an opposition leader has taken the presidential chair, and the second time for Buhari in power, as he led the country for 20 months between 1984 and 1985 after leading a coup.

Buhari's All progressive Congress (ACP) received 15m votes, representing 53.2% of the total votes, while Jonathan's People's Democratic party got 12,8m votes.

Although early reports pointed out that Jonathan had recognised his defeat, and had even congratulated the new elected president, he announced on Wednesday that he would appeal the voting outcome. This moves follows his party's rejection to sign the results official record.