Opposition leader Nelson Chamisa, from the MDC Alliance, has called the Zimbabwe election result a "coup" against the will of the people.

"Yesterday's coup against your will is temporary," he said at a press conference in the capital, Harare, which was delayed by riot police.

He said they had "back-ups" of voter tallies, which he alleged the ruling Zanu-PF wanted to destroy when police raided the MDC headquarters on Thursday.

President Emmerson Mnangagwa won the vote with 50.8% of the vote, the Zimbabwe Electoral Commission announced on Thursday evening.

The president avoided a run-off by just 36,464 votes out of more than 4.8 million cast.