President Felipe Calderón of Mexico has replaced his Justice Minister Eduardo Medina Mora. While no official reason has been given for the move, observers attribute it to the failure of the government's campaign against the country's drug cartels.

When he was elected president three years ago, Mr Calderón declared war on the drugs mafia, which is mainly active in the border region with the United States. Yet despite deploying thousands of troops, the president has not been able to put an end to the high level of violent drug-related crime which has claimed the lives of over 13,000 Mexicans since the end of 2006.

A number of cartel leaders have been arrested but the most wanted man in Mexico is still on the loose: Joaquin Guzmán, alias "El Chapo", the head of the powerful Sinaloa cartel.