The country’s election commission announced that with 91.1 percent of polling stations reporting results, Museveni had 58.8 percent of votes, while former popstar Bobi Wine had 34.5 percent.
Final results are expected by Saturday afternoon.
Wine, 38, meanwhile was on track to see his newly formed National Unity Platform (NUP) become the main opposition party in Parliament, notably winning eight of nine constituencies in the capital Kampala.
The poll followed one of the most violent campaigns in years, with harassment and arrests of the opposition, attacks on the media and the deaths of at least 54 people.
Thursday’s election took place in apparent calm, but under the oppressive presence of soldiers and riot police and an internet blackout which has now entered its fourth day.
However Wine has alleged widespread fraud such as ballot box stuffing and said his party agents had in some places been beaten and chased away from polling stations.
“Whatever is being declared is a complete sham, we reject it and we dissociate ourselves with it,” he said on Friday.
Wine, whose real name is Robert Kyagulanyi, promised to provide video evidence once the internet was restored.
Election commission chairman Justice Simon Mugenyi Byabakama said “the onus is on candidate Kyagulanyi to show how votes are rigged.”
Tibor Nagy, the top US diplomat for Africa, said on Twitter that the vote was “fundamentally flawed”, citing the denial of accreditation to election observers and “violence and harassment of opposition figures”.
“We continue to urge restraint and rejection of violence by all actors as Uganda’s election results are announced. The immediate and full restoration of Internet connectivity is essential.”
Wine’s home remained sealed off by soldiers and police on Saturday, after he told AFP Friday evening that security forces had breached the fence around his home and he felt under “siege”
“They jumped over my fence. They came inside my compound. I feel threatened,” said the 38-year-old.
The army’s deputy spokesman Deo Akiiki said the soldiers were there for “his own security and the security of people around him”.
Police have advised people not to go out to celebrate or protest when results are announced citing draconian Covid-19 regulations which have regularly been used to crack down on the opposition.
35 years of Museveni
Museveni has ruled Uganda without pause since seizing control in 1986, when he helped to end years of tyranny under Idi Amin and Milton Obote. He is one of Africa’s longest serving leaders.
Once hailed for his commitment to good governance, the former rebel leader has crushed any opposition and tweaked the constitution to allow himself to run again and again.
And for many in the country, where the median age is 16 and most have known only one president, Museveni’s glory days are no longer relevant or sufficient.
Wine, with his humble origins in a slum and popular songs about economic and social injustice, struck a cord with young people, but observers say the odds were stacked against him with Museveni’s powerful grip on the state.
The election took place with no major international observer mission aside from the African Union, with the United States saying too many of its staff were denied permission to monitor the vote.
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