Rwandan and Congolese groups opposed to Rwandan President Paul Kagame's rule asked the International Criminal Court on Friday to investigate him for war crimes for allegedly backing rebel groups in eastern Congo.

A small group gathered outside the court in The Hague, Netherlands, with banners reading "Kagame Assassin," and "Freedom for Congo."

The gesture is mostly symbolic, as it is up to Court Prosecutor Fatou Bensouda to investigate Kagame. She is already probing members of the M23 rebel group in eastern Congo that formed this April with alleged ties to his regime across the border. Kagame denies involvement.

Christopher Black, a lawyer for the groups that want Kagame investigated, said Friday that Bensouda need only turn to the International Criminal Tribunal for Rwanda to launch a case against Kagame, asserting it has a "mountain" of evidence against him in its archives. Kagame has been an important military leader in Rwanda since 1990 and its president since 2000.

The U.N.-backed Rwanda tribunal, based in Tanzania, never pressed charges against Kagame, long seen as key ally for Western powers in central Africa.

But Friday's demand for action follows a report issued by the U.N. in July that accused high-ranking Rwandan officials of helping to create, arm and support the current M23 rebellion within Congo.

A bipartisan group of U.S. legislators on Aug. 3 also sent a strongly worded letter to Kagame saying they are "absolutely convinced that Rwanda is involved in supporting the unrest" in eastern Congo.

Several Western countries, including Germany and the Netherlands, have suspended some aid to Rwanda as a result.

Kagame, an ethnic Tutsi, has a history of intervention in eastern Congo. Rwanda first invaded its neighbor to the west in 1996, pursuing Rwandan Hutus who fled after committing the 1994 Rwandan genocide of some 800,000 Tutsis. It took Kagame a year to admit that his troops had invaded eastern Congo.

The move was in part self-defense as U.N. and Western powers failed to act while the "genocidaires" used the cover of massive refugee camps to arm themselves and make incursions into Rwanda.

Remnants of the genociders in Congo formed the Democratic Front for the Liberation of Rwanda, or FDLR, which has become part of a never-ending cycle of violence in eastern Congo. Kagame's government fears they could one day invade Rwanda.

In response, Kagame first orchestrated a rebellion of Congolese Tutsis led by Rwandan soldiers that toppled Congo's longtime dictatorship and precipitated back-to-back civil wars that drew in the armies of eight African nations in a scramble for Congo's massive mineral resources. Some 5 million people died before the war ended in 2003.

After Rwandan troops withdrew under international pressure, Kagame turned to proxies, supporting a Congolese Tutsi-led rebellion that engulfed east Congo in 2008. To end that insurgency, Congo's President Joseph Kabila signed a pact allowing the rebels to integrate into the army and for Rwandan troops to come into Congo for three months to again hunt down the FDLR.

The mutinying soldiers who began this year's insurgency were once part of the 2008 rebellion.

Protestors outside the International Criminal Court Friday seemed most concerned with Kagame's possible involvement in events of the 1990s, especially leading up to and after the 1994 genocide. But the ICC would only have jurisdiction over any war crimes he committed after the court came into being in 2002.