Reproduction of a letter to the National Commission of Human Rights from criminals, drug dealers, murderers and kidnappers in "El Altiplano," Mexico's highest-security prison. Ronaldo Schemidt/AFP/Getty Images hide caption

itoggle caption Ronaldo Schemidt/AFP/Getty Images

A platform owned by Mexico's state-run oil company Pemex is seen off the Bay of Campeche in the Gulf of Mexico. The country has recently opened up its energy sector to foreign investors. Victor Ruiz/Reuters/Landov hide caption

itoggle caption Victor Ruiz/Reuters/Landov

The alleged leader of the Zetas drug cartel, Omar Trevino Morales, is taken under custody to be presented to the press at the Attorney General Office's hangar at the airport in Mexico City, on March 4. Mexican authorities captured Trevino Wednesday, dealing a blow to the feared gang and giving the embattled government a second major arrest in a week. Omar Torres/AFP/Getty Images hide caption

itoggle caption Omar Torres/AFP/Getty Images

The 2,100-person Tijuana municipal police force is one of Mexico's largest. It's also the first in the country to employ body cameras for its officers. Washington Post/Getty Images hide caption

itoggle caption Washington Post/Getty Images

In 2013, the U.S. imported about 2 million tons of Coronas and Modelos, making beer Mexico's largest agricultural export to the U.S., according to a USDA report. Scott Olson/Getty Images hide caption

itoggle caption Scott Olson/Getty Images

Mexico's President Enrique Pena Nieto gestures after delivering a speech at the Los Pinos presidential Palace in Mexico City on Tuesday. Yuri Cortez /AFP/Getty Images hide caption

itoggle caption Yuri Cortez /AFP/Getty Images

In this video frame grab image taken from Milenio TV via APTN, police look at the scene where a gas tank truck exploded outside a maternity and children's hospital in Mexico City on Thursday. AP hide caption

itoggle caption AP

Jasjit Kaur Singh, an Indian chef, cooks kaala channa, a traditional spicy Sikh dish. A psychologist says that children who grow up in cultures with lots of spicy food are taught to like spice early on. Richard Lautens/Toronto Star via Getty Images hide caption

itoggle caption Richard Lautens/Toronto Star via Getty Images

La Roca restaurant in Nogales, Mexico, draws a mix of American tourists and locals. It used to have an American bank account and credit card until the bank closed the account. Jude Joffe-Block/KJZZ hide caption

itoggle caption Jude Joffe-Block/KJZZ