A group of dissident Mexican army officers has appealed to President Ernesto Zedillo, to tackle human rights abuses in the military.

In an open letter, the group's leader, Lieutenant-Colonel Hildegardo Gomez, said conditions had got worse since around fifty officers staged a protest in Mexico City last month.

Lieutenant-Colonel Gomez went into hiding after the demonstration and faces charges of insubordination.

In the letter he said basic rights were being ignored, and he called for the creation of a special commission to review specific cases of injustice.

In one case, a former army general was sentenced to fourteen years in prison by army court-martial for proposing an independent ombudsman to monitor human rights in the armed forces.

The severity of the sentence was criticised by the human rights group, Amnesty International.