Earlier this month, a mural of civil rights leader Dolores Huerta was defaced in San Francisco.

“It’s messed up, man,” Suaro Luis Cervantes, the artist behind the piece in the Mission District, told CBS affiliate KPIX5.

The vandal, who also marred murals of Nelson Mandela and Sitting Bull, sprayed black paint over the Mexican-American labor rights leader’s face.

Gonzales called the perpetrator “sick.”

“Whoever you are, you’re a sick puppy. Sick! On top of racist,” he said. “I can’t prove that it’s a racist person, but somebody who definitely doesn’t like the culture.”

He spent several hours removing the paint and re-working his original piece. According to the news site, the work and materials to touch up the sizable mural can cost about $1,000. However, the artist, who made the piece a few years back, has always worked on the mural free of charge.

While upset about the damage, the artist had a few tips for the vandal.

“I wish peace and love get into your heart. And cut the crazy s*** before somebody stomps you, seriously,” Gonzales said.

The mural can be found on 24th and York in the Mission District.