MADRID, Spain (CNN) -- A Spanish judge Wednesday indicted 40 current or former Rwandan military officers for several counts of genocide and human rights abuses during the 1990s when several million Rwandans died or disappeared.

General James Kabarebe, left, is one of the 40 indicted for several counts of genocide and human rights abuses.

The judge issued international arrest warrants against the 40, including Gen. James Kabarebe, whom the judge said is believed to be the chief of staff of Rwanda's military; Gen. Kayumba Nyamwasa, whom the judge said is believed to be Rwanda's ambassador to India; and Lt. Col. Rugumya Gacinya, whom the judge said is believed to be a military attaches at Rwanda's embassy in Washington, according to court documents viewed by CNN

Rwanda does not have an extradition treaty with Spain, a court spokeswoman told CNN.

The indictments against the 40 are for "crimes of genocide, human rights abuses and terrorism," during the 1990s in Rwanda, "when more than four million Rwandans were killed or disappeared under an extermination plan for ethnic and/or political reasons," the court documents said.

The judge, Fernando Andreu, named eight Spaniards who died or disappeared during those tumultuous years in Rwanda. Their plight prompted his investigation at Spain's National Court in Madrid, which previously has investigated human rights violations against Spaniards during past military regimes in Chile, Argentina and elsewhere.

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Five of the Spanish victims were missionaries. The bodies of four of them were found in late 1996 after they were tortured, and shot or hacked to death with machetes, the documents said, while a fifth is still missing.

Three other Spaniards were shot to death in early 1997 while working for a non-profit medical group providing aid to Hutu refugees in Rwanda, the documents said.

The majority of the victims during the wave of terror, the documents said, were Hutu Rwandan refugees or Congolese civilians, mainly Hutus as well.

The judge did not indict Rwanda's president, Paul Kagame, because he has immunity as head of state, the documents said. But the judge also found evidence of criminal activity by Kagame, based on the testimony of an informant who told the judge he previously worked on Kagame's security detail, the documents said.

In preparing the indictments, the judge heard testimony from 22 people who said they witnessed the horrors in Rwanda in the 1990s. All of them live in exile, mainly in Europe, and all have changed their identity for security reasons, except Maria Beatrice Umutesi, who lives in Belgium and has written a book about the killings, the documents said.

The documents included a 182-page indictment and two accompanying summary documents. E-mail to a friend

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