The 15-year-old U.S. citizen who confessed to killing four people and hanging their beheaded bodies off a bridge is now going to prison in Mexico. On Tuesday, a judge sentenced Edgar "El Ponchis" Jimenez Lugo to four years in prison--the maximum allowed for a minor according to Mexican law--on homicide, kidnapping, and drugs and weapons charges. Born in San Diego but raised in Mexico, Lugo was arrested last December when trying to fly back into the United States with his sister to meet their mother and told reporters thereafter that he'd started killing at age 11 after drug cartels drugged and threatened him. The arrest came after a video of two young boys posing next to corpses and guns surfaced on YouTube in November--Lugo was apparently an accomplice to those murders.

The horrific images became an illustration for how Mexican drug cartels recruited an increasing number of adolescents to do their dirty work. The New York Times reports some sobering numbers:

Of the more than 35,000 people killed in organized-crime-related violence since President Felipe Calderón began a crackdown in 2006, an estimated 5 percent have been minors.

The Mexico attorney general’s office, in an October report, said the number of minors charged with drug-related crimes had increased to 810 in 2009 from 482 in 2006, a period in which thousands of federal police officers and soldiers swarmed several states to reduce crime.

WikiLeaks cables showing conversations between U.S. and Mexican authorities reveal "prosecution rates for organized crime-related offenses are dismal; 2% of those detained are brought" to court.