The vandalism was found at about 10:55 a.m. Saturday at the Weed Beach Complex, police said.
Officers saw several racially charged markings made at the courts, police said.
"One marking was in the shape of a 'swastika' and the other was a racial slur," police said in a statement. "A third word was observed but was illegible."
The swastika was about 18 inches by 18 inches in size, and the derogatory racial slur was about 12 inches by 36 inches, police said.
"The markings were made in chalk, therefore responding officers were able to completely clean the markings immediately," police said.
There was no permanent damage to the tennis court, police said.
Officers were unsuccessful in locating any witnesses or further evidence, police said.
There are no suspects at this time, police said.
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