HARARE, Zimbabwe — Police in riot gear on Friday tried to break up a news conference by Zimbabwe’s opposition leader, Nelson Chamisa, at which he said the narrow election victory of President Emmerson Mnangagwa was fraudulent and ‘‘stolen from the people.’’
Chamisa said his party would challenge the result in court on grounds of vote rigging and other irregularities.
Mnangagwa, head of the ruling ZANU-PF party, praised the election as ‘‘free, fair and credible . . . an unprecedented flowering of freedom and democracy in our beloved homeland.’’ Many voters were hoping the election would allow the country to move beyond President Robert Mugabe’s decadeslong authoritarian rule.
Mnangagwa won Monday’s election with just over 50 percent of the vote. The election was mostly peaceful but turned deadly 48 hours later when the military fired on protesters in the capital, Harare, killing six people.
On Friday, police banged batons on their shields in an attempt to disrupt the press conference, in front of dozens of reporters and international election observers.
The officers stopped short of breaking up the event by force because cameras were present, the Associated Press reported, but their deployment called to mind the suppression of the opposition under Mugabe’s rule, which Mnangagwa has pledged to change.
Chamisa, leader of the Movement for Democratic Change (MDC), spoke once police withdrew. ‘‘We won this election,’’ Chamisa said, declaring ‘‘a day of mourning . . . for democracy.’’ He alleged that his supporters faced violence and harassment at the polls, as well as claiming vote-rigging.
Election officials declared early Friday that Mnangagwa would stay on as president, a role he has held since a military intervention last November forced Mugabe to resign.
They said Mnangagwa, 75, avoided a runoff with Chamisa, 40, by a razor-thin margin of less than a percentage point, with just 50.8 percent of the total vote. His party, ZANU-PF, also won a two-thirds majority in Parliament
But Chamisa said the MDC’s count showed that it won 56 percent of the vote.
Monday’s election was largely peaceful, but by Wednesday, downtown Harare was a war zone.
Young men chanting slogans of the opposition went on a looting and vandalizing rampage through the center of town before the army — seen by many as aligned with Mnangagwa — opened fire killing six and injuring many more.
It remained unclear whether Mnangagwa or ZANU-PF played any role in their deployment.
The next day Harare was deserted as security forces patrolled the streets, but by Friday, Harare’s people went back to work, their opinions sharply divided over the president that some see as their savior while others fear he is even worse than Mugabe.
“E.D. was there. He knows all the mistakes that Mugabe made,’’ said Lovemore Katungwa, using Mnangagwa’s initials, as most do here. ‘‘We are celebrating because Zimbabwe can now join the brotherhood of nations.’’
Katungwa stood beside his friend Siwa Kadema in front of their decrepit apartment block built by the Mugabe government, which has no running water or trash collection.
Both are 38, and were born on the eve of Zimbabwe’s independence from white rule, the result of a struggle that gave both Mugabe and Mnangagwa the badge of liberation hero.
‘‘My parents had the whites, and we’ve had Mugabe,’’ said Kadema. ‘‘That is why today is a happy day. We will get the change we need.’’
Zimbabwe’s economy is in a precarious state. After runaway inflation brought Zimbabweans trillion-dollar currency notes in 2009, Mugabe adopted the US dollar which is now in short supply here. Many in rural areas have reverted to barter. Others mostly get by using government bond notes.
Mnangagwa centered his campaign on attracting foreign investment and creating jobs. But millions have already emigrated, and some Chamisa supporters were only half-joking on Friday morning when they discussed joining that wave.
Takudzwa Wazara sat in his car listening to talk radio and searching Google for visa application procedures on his phone. He shook his head.
‘‘This country, this election, my life — it’s a farce, man!’’ said Wazara. ‘‘I just can’t shake the feeling that we are all being made into fools.’’
Like many Chamisa supporters, Wazara doubts the integrity of the election.
Civil rights groups have documented more than a thousand cases of intimidation, vote-buying, and other electoral malpractice. Countless rumors of the various ways ZANU-PF ‘‘cooked’’ the results have circulated on social media, which Zimbabweans use prolifically.
Chamisa tweeted on Friday morning that the Zimbabwe Election Commission denied the MDC its right to check the official results against their own.
On Thursday, police produced a warrant to search the MDC’s headquarters in what party officials claimed was an attempt to confiscate their data on ‘‘the real results.’’
Wednesday’s harsh crackdown on MDC supporters also gave some people a reason to believe that Mnangagwa would work closely with the army to clamp down on dissent, much as Mugabe did.
For years, Mnangagwa was Zimbabwe’s defense minister and head of intelligence.
He is accused of orchestrating some of Mugabe’s greatest atrocities, including massacres of tens of thousands of members of a minority ethnic group, the razing of neighborhoods with major opposition support, and the campaign of violence that forced the MDC to boycott a runoff in the 2008 elections.