Authorities in the southern Mexican state of Guerrero must cancel arrest warrants for five indigenous activists after their colleague was set free because of irregularities in the case against them, Amnesty International said.

Prisoner of conscience Maximino García Catarino, one of the leaders of the Organization for the Future of the Mixtec Peoples (OFPM), was freed yesterday after two months in detention.

He was arrested on false murder charges on 21 January and subjected to an unfair trial.

Guerrero's Superior Court set him free after finding that a lower court had ordered his detention and trial without reliable evidence. However, the arrest warrants for the five other activists falsely accused of the February 2011 murder of Juan Teodoro García remain in force.

“By ordering Maximino García Catarino’s release after reviewing the case, Guerrero’s judicial authorities have recognised the injustice of his detention and discredited the basis for his detention and prosecution,” said Rupert Knox, Mexico Researcher at Amnesty International.

“The authorities must now overturn the arrest warrants for the other five indigenous men who were falsely accused and ensure all OFPM members and their families are granted protection in line with their wishes. If the arrest warrants are carried out, we will consider them prisoners of conscience.”

On 21 January, Guerrero state judicial police arrested Maximino García Catarino at his home.

According to a local NGO, the police failed to provide an arrest warrant or a reason for his arrest. He was later accused of the February 2011 murder of Juan Teodoro García, a member of a neighbouring community.

Police questioned Maximino García Catarino about other OFPM leaders, beating him when he refused to answer.

The indigenous activist was then transferred to the local prison, but was not brought before a judge until 23 January. His subsequent trial ignored defence evidence indicating that he could not have committed the crime and overlooked irregularities in the prosecution’s case.

Amnesty International calls on Guerrero’s authorities to carry out a full and impartial investigation into the murder of Juan Teodoro García to establish the facts and bring the real perpetrators to justice.

The organization believes that Maximino García Catarino’s trial and imprisonment was in reprisal for legitimate human rights activism on behalf of his indigenous community.

Human rights organizations have documented cases of other indigenous activists in Guerrero being denied fair trials and facing prolonged periods in prison on the basis of fabricated criminal charges.

“This case shouldn’t stop at the Superior Court’s ruling – the police, the public prosecutor and judicial officials who had a role in Maximino García Catarino’s wrongful detention and prosecution must be held accountable,” said Rupert Knox.

“This is essential for stamping out impunity for public officials who abuse the justice system to persecute activists and human rights defenders in Guerrero.”