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By Emma Thomasson
THE HAGUE, July 3 (Reuters) - The International Criminal Court took custody on Thursday of its highest-profile suspect to date -- Congolese former rebel warlord and vice-president Jean-Pierre Bemba, who was arrested in Belgium in May.
The transfer of Bemba, accused of leading Congolese rebels in a campaign of rape and torture in the Central African Republic in 2002 and 2003, is a welcome boost to the court after judges ordered the release of its first suspect on Wednesday.
The decision to halt proceedings against Congolese militia leader Thomas Lubanga -- who will stay in detention pending a prosecution appeal -- was seen as a major blow for the world's first permanent warcrimes court, set up in 2002.
ICC Prosecutor Luis Moreno-Ocampo announced Bemba's transfer at a conference to celebrate the 10th anniversary of the signing of the court's founding treaty and promised justice for the victims of "massive sexual violence".
"There will be no impunity," he said. "We cannot bring back those who were killed or died of AIDS after being violated, but I am hopeful that we will bring justice for the victims."
Bemba, who was defeated by Joseph Kabila in Democratic Republic of Congo's (DRC) 2006 presidential election, is being held at a detention centre near The Hague.
He joins Lubanga and two other alleged Congolese warlords also indicted by the ICC as well as former Liberian President Charles Taylor, who is being held in the same prison but tried by the separate U.N.-backed Special Court for Sierra Leone.
The ICC was set up as a permanent successor to the temporary war crimes tribunals like those for Sierra Leone, Rwanda and the former Yugoslavia. So far, 106 countries have signed up to the court, mostly in Europe, Africa and Latin America.
Bemba's is accused of crimes including rape and murder committed when his MLC insurgents intervened in Central African Republic. The MLC also fought in Congo's 1998-2003 war and Bemba served as a vice-president to Kabila in the post-war transition.
Bemba, who has denied the allegations, fled into exile in Portugal last year saying he feared for his life in Congo. His fighters had battled in the streets of Kinshasa with Kabila's presidential guards in clashes that killed several hundred.
Richard Dicker from Human Rights Watch called Bemba's arrival in The Hague a "terrific moment" for victims in Central African Republic but said the court should widen its probe.
"It's important for the prosecution to look into allegations of crimes committed by Mr Bemba in the DRC and to go further up the chain of command in the DRC to look also into members of the current government accused of horrific crimes," he said.
The most senior figure to be arrested by the ICC so far, Bemba's arrival in The Hague comes a day after the prosecution suffered a major setback when judges ordered Lubanga's release.
Lubanga remains in custody pending a prosecution appeal, but judges have put his trial -- due to be the new court's first -- on hold as his defence cannot view some evidence that the United Nations wants to keep confidential to protect its sources.
Prosecutor Moreno-Ocampo said on Thursday he hoped a solution could be found in the next couple of weeks so the trial could finally get under way, while respecting Lubanga's rights.
"I am absolutely confident that there will be justice for Thomas Lubanga's victims," he said. "The court is building the foundations of an international criminal justice system and a fair trial is the cornerstone of that." (Editing by Caroline Drees)