Sixteen police officers were arrested in San Fernando, Mexico, on Thursday for allegedly protecting those responsible for the mass graves found earlier this month. Attorney General Marisela Morales said the police officers have been working with the Zetas drug cartel to cover up the murders. Authorities uncovered 10 more bodies from the mass graves Wednesday and Thursday, setting the total number of bodies at 126. Investigators said 17 people were arrested for participating in the executions. Authorities first discovered the mass graves earlier this month during an investigation into a report of the kidnapping of passengers from a bus in late March.