The United States has said it is "disturbed by irregularities observed during voting" in Rwanda's election, which long-time president Paul Kagame won with nearly 99% of the vote.
The US state department reiterated "long-standing concerns over the integrity of the vote-tabulation process".
Mr Kagame easily won a third term in office following an election which he had called a "formality".
He will have another seven years as president of the small East African nation praised for its economic performance but criticised for its silencing of opponents.
Electoral authorities said Mr Kagame won 98.63% of the vote. Neither of his two challengers won a full percentage point.
The US statement also said it remains "concerned by the lack of transparency in determining the eligibility of prospective candidates", and it commended Rwanda's media for reporting on complaints of harassment of some opposition candidates.
Mr Kagame faced two challengers, while three others were disqualified for allegedly failing to fulfil requirements including collecting enough signatures.
He told jubilant supporters: "This election was criticised so much due to me continuing to be your leader, especially people from outside the country because they oppose the will of Rwandans.
"But Rwandans have shown that it was not manipulated by anyone but their own will."
Mr Kagame has led the country of 12 million people since his rebels helped to end its genocide in 1994 in which more than 800,000 Tutsis and moderate Hutus were massacred by Hutu extremists.
The 59-year-old president has been praised for the country's economic growth, but human rights groups accuse his government of using state powers to silence any opposition. Rwandan authorities, including the president, deny this.
A constitutional amendment in 2015 allows Mr Kagame to stay in power until 2034 if he pursues it.
The United States, a key Rwanda ally, opposed the change to the constitution. Mr Kagame has accused some Western diplomats of meddling in the country's affairs.
He was running against Frank Habineza of the Democratic Green Party of Rwanda - the only permitted opposition party - and independent candidate and former journalist Philippe Mpayimana.
Three potential candidates were disqualified for allegedly failing to fulfil requirements, including collecting enough signatures.
Mr Mpayimana received just 0.73% of the vote, while Mr Habineza took 0.47%.
Well over 90% of Rwanda's 6.9 million registered voters cast their ballots, according to the Rwanda Electoral Commission.
In Rwanda's capital, Kigali, there had been little hint of the coming vote.
Candidates had been barred from putting campaign posters in most public places, including schools and hospitals. The electoral commission vetted candidates' campaign messages, warning that their social media accounts could be blocked otherwise.
Two decades of often deadly attacks on political opponents, journalists and rights activists created a "climate of fear" ahead of Rwanda's election, Amnesty International said in a report last month.
In 2010, Mr Kagame won election with 93% of the vote.
In July, he told a campaign rally that "the day of the presidential elections will just be a formality".