SUFFERING IN CENTRAL AFRICA : Rwanda Makes Pledge on Human Rights : Africa: U.S. hails new leaders’ promise to turn over suspects to U.N. war crimes tribunal and punish acts of revenge.

Assistant Secretary of State John H. Shattuck, finding signals of improved stability in ravaged Rwanda, hailed the new Rwandan leaders Tuesday for promising to turn over suspected killers to a future U.N. war crimes tribunal.

Shattuck, who heads the State Department’s human rights division, also welcomed a promise by Paul Kagame, the Tutsi vice president and defense minister, that his forces would punish any vigilante acts of revenge against members of the Hutu tribe accused of taking part in the frenzy of killing during the last four months. Foreign humanitarian workers have estimated that half a million Rwandans, mostly Tutsis, died in the slaughter.

These pledges, made after meetings with Shattuck in Kigali and then repeated in an official letter to U.N. Secretary General Boutros Boutros-Ghali, were clearly designed to convince Hutus that it is safe to return to Rwanda and to reassure the outside world that the new government of Rwanda intends to rule within the bounds of international law.

But in a telephone interview from Nairobi, Shattuck declined to say whether he would advise Hutu refugees to leave their camps in Zaire and return to Rwanda. He said it is up to officials of humanitarian agencies to make that decision. But he called the pledges “very important signals to the improved stability of the situation in Rwanda.”

Asked if Kagame and Prime Minister Faustin Twagirimungu had acknowledged that news accounts of murderous reprisals against Hutus are true, Shattuck said that the Rwandans had said only that they would punish those responsible if such acts occurred.

In the letter to Boutros-Ghali, Justice Minister Alphonse-Marie Mkubito urged the United Nations to create a tribunal swiftly so suspects would not be detained “for an unreasonable time period before trial.”

The Security Council, which has not yet established a tribunal, recently created a commission to gather evidence of genocide and other violations of international law in Rwanda. The commission has four months to finish its work. But Mkubito said it is imperative that the commission conclude its work expeditiously, well before the four-month deadline.

Mkubito said the Security Council should follow the pattern set when it created the Balkans War Crimes Tribunal. Set up more than a year ago, the Balkans tribunal has moved slowly and its prosecutor does not expect to issue any indictments until almost the end of this year.

The letter to Boutros-Ghali also promised that the new Rwandan leaders, who routed the Hutu-dominated army last month, “intend to make every effort to prevent summary executions and other acts of vigilante justice and to arrest those who commit acts of revenge.”