As brutal drug violence in the Mexican states of Michoacán and Guerrero continues, a Mexican prosecutor is claiming that vigilante groups supposedly battling drug cartels alongside the government have been extensively infiltrated by criminals.

According to ABC News, Michoacán state prosecutor Jose Martin Godoy told local media on December 29 that about half the vigilante movement’s leaders were honest, but the other half were drug traffickers or other criminals.

“In the self-defense groups, half of them rose up to create conditions of peace and tranquility and detain the criminal groups, but the other half, and the public knows this, were the well-known ‘forgiven ones’ who were part of a criminal group,” Godoy said. “There were a lot of people taken in to these (vigilante) groups, who in the end were involved in the criminal activities, in (synthetic drug) laboratories and drug trafficking.”

Vigilante groups rose up several years ago in these states in response to the Mexican government’s inability to control cartel activities. Initially, the militias met with much success, driving groups like the Knights Templar out of many villages and towns and reestablishing some sense of peace and order.

However, there has long been evidence in these states that neighborhood militias were being infiltrated by individuals belonging to rival cartels with an interest in killing the same people as the vigilantes. For example, if one militia was actively fighting the Knights Templar in Michoacán, they were likely to have members belonging to the Knights’ rival Cartel de Jalisco.

Godoy’s statement comes shortly after the bullet-riddled body of Carlos “El Tisico” Rosales Mendoza, the founder of La Familia Michoacana (the predecessor of the Knights Templar), was discovered alongside a Mexican highway. “Everything indicates that recently, he (Rosales Mendoza) had begun to have contact with some leaders of the self-defense group, he began to have meetings,” said Godoy.

Sylvia Longmire is a service-disabled veteran, border security expert, and Contributing Editor for Breitbart Texas. You can read more about cross-border issues in her latest book, Border Insecurity: Why Big Money, Fences, and Drones Aren’t Making Us Safer.