On 24 August 2000, a man who calls himself Ricardo Miguel Cavallo, alleged to have been responsible for torture in Argentina during the military government (1976-1983), was arrested in Cancun as he was about to leave for Buenos Aires. He remains in custody in Mexico pending a prompt judicial determination whether extradition proceedings or criminal proceeding should be instituted against him.

'The action taken by the Mexican authorities is in line with Mexico's obligations under the Convention against Torture and Other Cruel Inhuman or Degrading Treatment or Punishment,' Amnesty International said, welcoming the decision.

'If this person was indeed responsible for acts of torture, the next step must be for him to be brought to justice,' the organisation added.

Because of their scale and gravity, the human rights violations committed in Argentina under the military rule, constitute crimes against humanity. Any person who commits such crimes is subject to international criminal responsibility and sanction, as recognised in numerous international instruments such as the Charter of the Nuremberg Tribunal, the Statutes of the International Criminal Tribunals for the former Yugoslavia and Rwanda and the Rome Statute of the International Criminal Court. Compliance with superior orders does not exempt perpetrators from criminal responsibility.

Moreover, these are crimes over which any state may - and, Amnesty International believes, must - exercise universal jurisdiction regardless of where they were committed, the nationality of the perpetrators or the victims, the rank of the person responsible or the date they were committed.

'After all these years, it is high time for the victims of torture in Argentina to see that their plea has not been forgotten and that justice can still be done,' Amnesty International said.

Background The Mexican federal courts have universal jurisdiction in cases, such as torture, where this is provided for by an international treaty. Article 7 of the Convention against Torture requires Mexico when a suspect is found in its territory to extradite that person or to submit the case to its own authorities for the purpose of prosecution.

A Spanish judge from the Audiencia Nacional, Spanish National Court, has ordered an international warrant of arrest against Cavallo within the frame of the investigations initiated in 1996 by the court on crimes against humanity committed by the military government in Argentina. A French judge has filed an official request to Mexico to interrogate Cavallo in connection with human rights violations committed against 15 French citizens, including the 'disappearance' in 1977 of two French nuns.

It has been alleged that Cavallo was involved in the human rights violations committed at the Naval Mechanics School, Escuela de Mecánica de la Armada (ESMA), in Buenos Aires. The ESMA is one of the secret detention centres recorded in the report by the National Commission on Disappeared People, Comisión Nacional sobre la Desaparición de Personas, which was created in 1983 at the return of civilian government. Testimonies which have emerged over the years, including that of a former naval officer, confirmed documented information that persons held in custody were systematically tortured. Those in captivity were either killed under torture or sedated and thrown naked from navy aircraft into the Atlantic.

Kidnapped pregnant Women's rights's rightss rights's rights's rights's rights were not spared torture and most of them were allowed to give birth before being made ' disappear or killed while their babies were given to strangers, in many cases to childless couples connected to the armed forces or police. Argentine human rights organizations have estimated that between 4,000 and 5,000 'disappeared' detainees passed through the ESMA.

Most of those who committed these crimes remained unpunished by virtue of the Full Stop Law of 1986, the Law of Due Obedience of 1987 and the Presidential Pardons of 1989 and 1990.