Amnesty International UK Media Director, Lesley Warner, said:

'Activists from all over the world have the right to travel to Cancun to express their legitimate concerns about the way trade is regulated and its impact on social and economic rights. The Mexican authorities must ensure that those who come to demonstrate peacefully are allowed to meet with one another and express their opinions freely.'

In letters sent to President Vicente Fox Quesada and to the governor of the state of Quintana Roo, Lic Hendricks Diaz, Amnesty International called on the authorities to ensure that international standards on the use of force and firearms by the police are fully respected.

Amnesty International is urging the Mexican government to ensure that all policing officials behave in accordance with international policing standards. The letter to the Mexican President refers to Amnesty International's 10 basic human rights standards for law enforcement officials, a briefing prepared by Amnesty International in consultation with police officers and experts from many countries, which includes:

• use force only when strictly necessary and to the minimum extent required under the circumstances
• do not make arbitrary arrests; arrests to be made only when there are legal grounds for doing so and in accordance with lawful arrest procedures
• all detainees should have prompt access to legal representation and medical assistance if it is needed; there should be a prompt hearing by a judicial authority
• detainees should be treated humanely and not subject to any torture or ill-treatment.

To read 10 basic human rights standards for law enforcement officials visit: http://web.amnesty.org/library/index/engpol300041998