The International Criminal Court's chief prosecutor arrived in Kinshasa on Tuesday, the ICC said, following requests to investigate deadly violence in the Democratic Republic of Congo.
Prosecutor Fatou Bensouda is due to meet with government officials and judicial institutions and hold a press conference on Thursday, the court said.
In January, a European Parliament resolution urged "the ICC and the UN to investigate allegations" of crimes against humanity in Kasai in the centre of the Democratic Republic of Congo.
On March 1, the Congolese citizen movement Debout (Arise) also asked the ICC to investigate the crackdown on peaceful protests.
Sixteen people have been killed since December 31 as three marches, organised by the Catholic Church, were met with deadly force.
The marchers called on President Joseph Kabila to declare publicly that he would step down.
Kabila, in power since 2001, refused to leave office when his term expired in December 2016.
Elections, twice delayed, are due to be held on December 23, but opposition groups say they have little hope that the vote will be fair and credible.
Public rallies have been banned since September 2016, when dozens of demonstrators were killed.
Last year, at least 47 people were killed, according to a UN report seen by AFP last month.
Set up in 2002 in The Hague, the ICC is the world's only permanent war crimes court and acts to prosecute the worst abuses including genocide in places where national tribunals are unwilling or unable to act.
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