Security forces in the Democratic Republic of Congo have killed at least seven people at a protest calling for President Joseph Kabila to step down, UN peacekepers say.
Police said three people had died and two of the deaths were being investigated.
Church activists and opposition parties had backed the demonstration.
Under a deal reached a year ago, Mr Kabila was due to step down by the end of 2017.
That was a year after the end of his second term in office. An election to replace him has now been delayed until December 2018.
Catholic activists had called for protests after Sunday church services, but the Congolese authorities banned the demonstration.
Police used live ammunition and tear gas to prevent protesters from gathering at locations including churches.
Two men were shot dead outside a church in the capital Kinshasa, rights group Human Rights Watch said.
UN spokeswoman Florence Marchal said that in addition to the seven people shot dead in Kinshasa, another protester had been killed in the central city of Kananga,
More than 120 people had been arrested, she said.
She condemned the "use of force against peaceful demonstrators" and the "violent suppression of fundamental rights and freedoms by security forces".
Mr Kabila has been in power since 2001. He was supposed to step down after his second and final term came to an end in 2016 but the vote to replace him was not held.
The failure to organise the polls led to a wave of deadly demonstrations by opposition supporters. The UN says dozens of people have been killed during anti-government protests over the past year.
A deal to create a transitional government brokered by the Catholic church collapsed because the government and the opposition were unable to agree on the power-sharing mechanism.
Eighteen militiamen are on trial in the east of the Democratic Republic of Congo on charges of raping 46 children.
Some of the victims from the village of Kavumu were just 18 months old.
The men allegedly targeted young girls between 2013 and 2016 because a spiritual adviser told them that the blood of virgins would grant them supernatural protection.
The alleged militia leader, Frederic Batumike, a provincial legislator, and the other defendants deny the charges.
Rights groups hope the trial will help to end a culture of rape as a tool of war in DR Congo.
"The start of the trial is a strong signal in the fight against impunity," Jean Chrysostome Kijana, an activist representing the victims, told Reuters news agency.
Proceedings started 10 hours late and lasted only 20 minutes on Thursday, during which time the defendants' names were read aloud, according to Reuters.
Advocacy groups have told Reuters that the case has been particularly difficult to investigate because the victims were so young.
"Their families were often asleep when the alleged rapes occurred," Reuters reports.
Villagers believed a magic powder was being used to induce sleep, investigative journalist Lauren Wolfe told BBC Newsday:
"I thought... Could they [the attackers] be using some kind of herbal anaesthetic? It actually turned out to be true. They were."
She said the militiamen had been illegally squatting on an "extremely fertile" plantation previously owned by a German botanist who was murdered in 2012.
Following more than 20 years of conflict, much of eastern DR Congo is under the control of various militia groups.
The Democratic Republic of Congo was labelled "the rape capital of the world" by Margot Wallstrom, the former UN special representative on sexual violence in conflict.
Writing in The Guardian, Wolfe says that two years ago "one UN official resigned out of frustration at the UN's continued failure to halt the atrocities" in Kavumu.
Democratic Republic of Congo’s electoral commission announced Wednesday that the vote to replace President Joseph Kabila expected by the end of the year will not happen before the start of 2019.
Kabila officially ended his term in office in December, but he was allowed to stay in exchange for guarantees that elections will be held.
The delay could be reduced "if we accept to use voting machines and if we change the electoral law," a commission spokesman told AFP.
Following a meeting of the UN Security Council in New York, French Ambassador Francois Delattre called on Kinshasa to quickly release a full timetable for what he said must be "credible" elections.
"The council expects a speedy publication of the electoral timetable and the implementation of the confidence-building measures. There is a consensus on this very important point," Delattre told reporters.
The Security Council called for elections to be organised this year in the DR Congo, in line with a political agreement reached between the government and opposition groups.
But diplomats privately acknowledged that holding polls in the vast African country in the coming three months would not be possible due to logistical hurdles.
Diplomats said they did not consider the latest statement from the electoral commission as a formal timetable, which they stressed must contain specific dates for the vote.