The organisation pledges to continue its international campaign for the immediate and unconditional release of the two peasant environmentalists.

'This case has once again exposed severe deficiencies in the Mexican judicial system and the apparent collusion between the Mexican State and local economic interests threatened by the environmentalists' campaigning in Guerrero state,' the organisation added.

'The Mexican authorities have wilfully disregarded the conclusive evidence of the innocence of these two men, thus failing to uphold the rule of law,' Amnesty International said.

Background Rodolfo Montiel and Teodoro Cabrera were illegally detained on 2 May 1999 by the 40th Infantry Battalion of the Mexican Army in the community of Pizotla, Guerrero state. While being held in the incommunicado custody of the military, the detainees were forced to sign self-incriminating confessions and were formally accused of drugs and firearms-related crimes. On 28 August 2000 Montiel was sentenced to six years and 10 months in jail, and Cabrera to 10 years. Their defence lawyers, from the Miguel Agustin Pro Juarez Human Rights Centre, will lodge an immediate appeal.

On 14 July, Mexico's National Commission on Human Rights, a governmental organisation, acknowledged that Rodolfo Montiel and Teodoro Cabrera had been illegally detained and tortured by members of the Mexican Army. The report also confirmed that the evidence on which the Military base their charges was planted. After examining Montiel and Cabrera, forensic experts from the Danish section of Physicians for Human Rights concluded that the physical signs and symptoms found coincided conclusively with the timing and methods of torture described by the two activists.

Rodolfo Montiel, one of the founding members of the Organisation of Campesino Environmentalists of the Sierra de Petatlan and Coyuca de Catalan, was a recipient of this year's Goldman Environmental Prize for his environmental campaigning.