The crash of a small plane carrying a self-defense group leader over the weekend in the western Mexican state of Michoacan was caused by pilot error, Government Secretary Miguel Angel Osorio Chong said Tuesday.

Jose Manuel Mireles Valverde, leader of the Self-Defense Groups Council of Michoacan, was injured when the small plane went down on Saturday night.

One person was killed and four others, including Mireles, were injured when the small plane made an emergency landing in La Huacana, a city in Michoacan.

The person who died in the crash was an associate of Mireles.

"It was the pilot's lack of skill, there are no signs of anything else, including an attack. I have absolutely nothing about that," Osorio Chong told Mexico City's Radio Fórmula.

Photographs of the aircraft do not show that it was attacked, the government secretary said.

Mireles, who is being treated at a Mexico City hospital, was airlifted to the capital by the government because "he has been hurting the cartels, especially the Templarios," Osorio Chong said.

The plane crash happened hours after the vigilante group led by Mireles entered Paracuaro, a city in the Tierra Caliente region, which straddles Michoacan, Guerrero and Mexico states.

The vigilantes clashed with gunmen suspected of being on the payroll of Los Caballeros Templarios, leaving a self-defense group member dead, security officials said.

The self-defense group members disarmed police in Paracuaro and formed a security council to protect the city.

Vigilante groups now control 13 cities and a community in Michoacan.

Some Mexican analysts say Michoacan is close to becoming a failed state because some areas are ungovernable due to the presence of drug traffickers and the emergence of vigilante groups. EFE