Reies Lopez Tijerina, a Pentecostal preacher-turned-radical-leader for the Chicano movement 50 years ago, died Monday.

Tijerina died at an El Paso, Texas hospital of natural causes, which was confirmed by the Tijerina family, Al Jazeera reports. He was 88.

Along with Chicano activists Cesar Chaves, Corky Gonzales and Jose Gutierrez, Tijerina is considered one of the "Four Horsemen of the Chicano Movement."

In 1963, the Chicano leader founded La Alianza Federal de Mercedes, which aimed to reclaim the Spanish and Mexican land grants held by Mexicans and American Indians in the Southwest before the Mexican-American War. By 1966, the group said they counted 20,000 members in the organization.

Although thought of by many Mexican-American students as a hero, the methods used by Tijerina and his organization were often controversial and frequently violent. He is often called the Malcolm X of the Chicano movement.

The activist was best known for his 1967 raid of the Tierra Amarilla courthouse. He and his followers raided the courthouse in an attempt to commit a citizen's arrest of the district attorney. This was after the attorney had eight members of Tijerina's organization arrested for organizing a protest over land grants. 

In the raid, a police officer and jailer were shot and wounded. The organization also beat a deputy and took the sheriff and a reporter hostage during the melee. They escaped the courthouse into the Kit Carson National Forest.

Tijerina was eventually arrested but acquitted of charges related to the raid. He later spent two years in prison for federal destruction of property.

After the raid, Mexican-American students became inspired to join the Chicano movement.  

Tijerina was born in Fall City, Texas in 1923 to migrant farmworkers. He is survived by his wife of 22 years, Esperanza, and his children.