Local media reported several corpses where thrown from the roof of the three story prison, while the terrified family members crowded outside

At least 20 inmates died inside the high security area of a prison in the border city of Ciudad Juarez yesterday in what looks to have been a massacre carried out by members of one gang against rivals.This is the latest of a series of bloodbaths in Mexican jails that have killed 83 prisoners in six months. They are associated with the drug wars outside which killed over 6,000 in 2008 and well over 1,000 so far this year.The different cartels are fighting each other for supremacy in strategic cities and states around the country, as well as fighting an unprecedented military-led crackdown launched by president Felipe Calderón two years ago. Juarez, just over the border from El Paso, Texas, is currently the most violent front in the wider war."The external conflict is being transferred to inside the prisons," said Enrique Torres, spokesman of the federal government's security operation in Juarez. "Organised crime looks for any space it can fill."
Torres said that the massacre started shortly after 6am when 14 members of a gang calling itself the Aztecas were escorted back to their cells after conjugal visits. Arriving at their module in a relatively low-security part of the building, they produced knives and forced the guards to unlock about 150 fellow gang members.Taking the wardens hostage, the Aztecas went directly to the high-security block and forced guards to open cells containing members of rival gangs called the Mexicles and the Artistas Asesinos. They then set about killing them.Some of the victims were murdered with the knives, others beaten to death and others killed with a home-made gun, Torres said.Local media reported several corpses where thrown from the roof of the three story prison, while the terrified family members crowded outside the prison gates looked on.The situation was eventually brought under control three hours after it started. Around 200 special forces agents from the militarised federal police, 50 soldiers, two helicopters, a plane, and unspecified numbers of state and municipal police were involved in the operation.