Graffiti artists, such as Charles "Chaz" Bojórquez, developed an original style of graffiti art known as West Coast Cholo style influenced by Mexican murals and pachuco "placas" (tags which indicate territorial boundaries) in the mid-20th century. In the 1960s, Chicano graffiti artists from San Antonio to L.A., especially in East LA, Whittier, and Boyle Heights, used the artform to challenge authority, tagging police cars, buildings, and subways as "a demonstration of their bravado and anger," understanding their work as "individual acts of pride or protest, gang declarations of territory or challenge, and weapons in a class war." Chicano graffiti artists wrote "con safos" (loosely translated to expressing a "so what" or "the same to you" attitude)—a common expression among Chicanos on the eastside of Los Angeles.