The Popular Revolutionary Army (EPR), a left-wing rebel group based in southern Mexico, announced Jan. 15 that it will give advanced warning of any future attacks to avoid injuries. The chances of such attacks in 2008 are high. The EPR emerged in 1996; it was involved in kidnapping and extortion in its early years. In recent years, it has avoided putting the general public at risk while attempting to tap into discontent over President Felipe Calderón’s contentious 2006 presidential victory and to build a more solid support base. The left-wing group continues to demand the release of two operatives, which it says Mexican security forces captured in the southern state of Oaxaca in May 2007. But the government continues to deny it is holding the two. EPR's 2007 series of attacks against state-owned energy company Petróleos Mexicanos (Pemex) caused hundreds of millions of dollars in damage due to lost production and natural gas cutoffs to hundreds of companies in central Mexico. The recent announcement mimics tactics employed by militant groups like ETA and the Irish Republican Army, which both phone in warnings ahead of impending bomb attacks. The announcement comes after government sources revealed in December 2007 that it was tracking the movements of up to four EPR cells. Given the vast extent of Pemex's infrastructure — which includes pipelines, refineries and state-owned power plants under Mexico's Federal Electricity Commission — and the military’s continued preoccupation with anti-drug operations, Mexican energy infrastructure continues to be highly vulnerable to attack. Transnational economic interests also could see an attack, given that EPR targeted a Sears store in Oaxaca in August 2007. Calderón is still struggling to strengthen intelligence services after neglect by the Fox administration, and his newly named interior minister may point toward a heightened focus on security. But the EPR is a small, apparently skilled group experienced at evading Mexico's security services. The risk of attack in 2008 on government-owned energy infrastructure and state and federal government offices is accordingly high.