The vandalism was discovered in Elands Bay, where cave paintings show stories of the ancient San's religious experiences and beliefs, The Cape Town, South Africa, Cape Times said.
Jane Moleleki, a provincial director of cultural affairs, said the vandalism would be investigated. Specialists were called in to assess the damage and determine whether the art can be restored.
"Rock art is our heritage in the Western Cape," she told the Times. "It has to be preserved and should be protected."