Hundreds of supporters of spurned Democratic Republic of Congo opposition candidate Martin Fayulu gathered in the capital on Friday to denounce what they called "the people's stolen victory" in the presidential election.A heavy police presence was on hand as Fayulu was expected to speak. A businessman and vocal campaigner against DRC's widespread corruption, Fayulu accuses outgoing President Joseph Kabila of making a backroom deal with the surprise declared winner, largely untested opposition leader Felix Tshisekedi.Fayulu has two days from the election announcement early Thursday to file a court challenge. The influential Catholic Church, the rare authority that many Congolese find trustworthy, says its 40,000 election observers found a different winner, and diplomats briefed on its findings say Fayulu easily won.Congolese now face the extraordinary situation of an election allegedly rigged in favor of the opposition after Kabila's ruling party candidate, Emmanuel Ramazani Shadary, did poorly in the polls."Change cannot be negotiated behind closed doors and power only comes from the ballot, there is no other way," said student Jean Otaba, 28. "You can see there is no massive celebration despite the announcement. That's because it is not the truth."This could be DRC's first peaceful, democratic transfer of power since independence in 1960, but observers have warned that a court challenge to the results could spin the long-troubled country into chaos. Some Fayulu supporters worried that the constitutional court could invalidate the election results, keeping Kabila in power until a new vote.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook. As night fell on Thursday, scores of police with automatic rifles and tear gas launchers were positioned along a road in Kinshasa leading to the Kingabwa neighborhood, a Fayulu stronghold. Elsewhere, the nation of 80 million has remained largely calm, though police said three people were killed in Kikwit city on Thursday as people protested the results. Some students protested in the city of Mbandaka on Friday.Internet service in DRC, cut off the day after the December 30 vote, had not yet been restored.Careful statements by the international community have not congratulated Tshisekedi, merely taking note of official results and urging peace and stability in a country with little of it. The United Nations Security Council was set to discuss DRC on Friday after officials with France, Belgium and Britain raised concerns.In a statement overnight, the United States said that "we await clarification of questions which have been raised regarding the electoral count" and it warned against violence."Imperfect elections which guarantee post-election stability are getting more accepted than credible elections that result in refusal of power transfer and conflict!" Arnold Tsunga, Africa director with the International Commission of Jurists rights group, mused on Twitter on Friday.Tshisekedi, who received 38% of the vote according to official results, had not been widely considered the leading candidate. Long in the shadow of his father, the late opposition leader Etienne Tshisekedi, he startled DRC last year by breaking away from the opposition's unity candidate, Fayulu, to stand on his own.Fayulu, a former Exxon manager and Kinshasa lawmaker, received 34% of the vote in the official results. He was a vocal activist during the turbulent two-year delay in DRC's election, insisting it was time for Kabila to go as many feared the president would find a way to stay in office and protect his vast assets obtained from DRC's staggering mineral wealth.Fayulu was backed by two popular opposition leaders barred by the government from running.The difference between Tshisekedi and Fayulu in official results was some 684 000 votes. Some observers said the 1 million voters who were barred at the last minute, with DRC's electoral commission blaming a deadly Ebola virus outbreak, could have made the difference. Elsewhere, election observers reported numerous problems including malfunctioning voting machines and polling stations that opened hours late.Several DRC analysts said it appeared Kabila made a quiet agreement with Tshisekedi, saying Fayulu would have posed more of a threat to his interests and allies and that Tshisekedi was more malleable. Tshisekedi took over as head of DRC's most prominent opposition party only in early 2018, a year after his father's death.After results were announced, Tshisekedi said Kabila would be an "important partner" in the power transition."Felix Tshisekedi has been compromised," said Tamuzi Mandar, a local official with Fayulu's Lamuka coalition. "What is finally revealed is that he is not opposition. His father was, but not him.""Felix betrayed the people by licking Kabila's plate," said Joel Ituka Kuzembe, 25, who said he spent nine months in prison for participating in the protests that demanded that Kabila step down.Kabila has ruled since 2001 in the Central African nation rich in the minerals key to smartphones around the world. He is barred from serving three consecutive terms but has hinted that he could run again in 2023."There is a lot of sadness in the country," said Bob Vonda, 35, a lawyer. "You can see people are not celebrating apart from a very small part. People feel they have been robbed."