(CNN)Vandals threw red paint on statues of Christopher Columbus in San Francisco and Providence, Rhode Island, as people around the US prepared to celebrate the Italian explorer.
Workers in San Francisco scrubbed away the paint on the monument Sunday and worked to remove graffiti that said "Destroy all monuments of genocide and kill all colonizers."
Many groups have called for the holiday to be renamed Indigenous Peoples' Day to recognize the native people who were driven out by European explorers. San Francisco is one of several cities that observes Indigenous Peoples' Day.
The San Francisco statue is near the Coit Tower, a popular tourist spot, and a lot of people were there on Sunday to watch the Blue Angels perform.
"It's really, really great from up here, but unfortunately whoever decided to deface this statue -- that's just a terrible thing to do," Steve Leiker told CNN affiliate KRON.
Gina Williams, who said her grandparents are part Apache, told KRON that she understood why someone might vandalize the statue, but said it was the wrong way to send a message.
"This was unnecessary," she told KRON. "These are our tax dollars that have to clean this. You made the mess -- do you realize it's still coming out of your pocket? People don't think. They just don't think."
Police are investigating.