In what appears to have been a string of politically motivated attacks, explosions rocked at least six oil and natural-gas pipelines in Mexico’s state of Veracruz on Monday. The pipelines that were hit are all owned by Mexico’s petro-monopoly Pemex and occurred at opposite ends of Veracruz state. Some 15,000 people were evacuated from various towns and cities near the explosions afterward as a precaution, though some have been allowed to return home. The Popular Revolutionary Army, or EPR, claimed responsibility for similar attacks in July but so far it’s unclear what, if any, involvement the guerrilla group may have had in the most recent bombings. While the explosions are expected to be expensive setbacks for Pemex, Mexico’s exports of roughly 1.4 million barrels of oil a day to the U.S. will apparently not be affected. Traveling in India, Mexican President Felipe Calderon promised the pipeline attackers would be caught and said that they “wish to impose by force their ideas on everyone else.” At least we think he was talking about the attackers.