Luanda/Kinshasa - US Secretary of State Hillary Rodham Clinton Monday arrived in conflict-hit Democratic Republic of Congo, where she is expected to call for an end to sexual violence against women.

While a bloody war in the sprawling Central African nation officially ended in 2003, various rebel groups have kept the conflict running in the eastern provinces.

The United Nations estimates that around 3,500 women have been raped by all parties to the conflict since the beginning of the year as government troops attempt to tackle a Rwandan Hutu rebel group.

On the fourth leg of her Africa tour, Clinton is on Tuesday expected to meet with victims of rape in the eastern city of Goma, where many internally displaced are still sheltering after being forced to flee their homes.

"I'll be in Goma, and I will be there primarily to speak out against the unspeakable violence against women and girls in eastern (DR) Congo," Clinton said Thursday during a forum in the Kenyan capital Nairobi. "It is the worst example of man's inhumanity to women."

Clinton is due to meet President Joseph Kabila in Goma, and is expected to push him to bring his troops into line.

The army late last year launched operations aimed at flushing out the Hutu rebel group, formed by the perpetrators of the 1994 Rwandan genocide.

New York-based Human Rights Watch said that instances of rape had increased dramatically since the offensive began and that the majority of the rapes it investigated were carried out by government troops.

More than five million people are estimated to have died as a result of the DR Congo's 1998-2003 conflict and its long aftermath, most of them from hunger and disease.

Observers have pointed out that the simmering conflict in the east of the country has been driven by illegal mining, which lines the pockets of the various militia and government troops.

Clinton emphasized this point, telling students in Nairobi that the trade in minerals was driving the violence.

"It's because there are mines in eastern (DR) Congo that produce the minerals that go into our cell phones and our other electronics," she said.

The secretary is Monday night expected to take part in a forum with students in the Congolese capital Kinshasa and dine with Congolese officials.

Earlier on Monday, Clinton was in Angola, where she met President Jose Eduardo dos Santos in Luanda and signed an agreement for increased US help in fighting AIDS.

Under the agreement, Washington is to increase by 10 million dollars its support for Angola's efforts to fight AIDS.

After her arrival from South Africa on Sunday, Clinton praised Angola for carrying out successful legislative elections in 2008, but urged Luanda to adopt a new constitution, investigate human rights issues and hold presidential elections.

The DR Congo is the fourth stage of Clinton's 11-day, seven- country Africa tour that began in Kenya on Tuesday.

After DR Congo, Clinton is expected to visit Nigeria, Liberia and Cape Verde.(dpa)