Members of the Irula tribe in the Nilgiri forests in Tamil Nadu are furious about the damage caused by trekkers and tourists to the rock paintings in Karikiyoor at Kil Kotagiri village, The Hindu reported on Monday.

The paintings, which are 5,000 years old, have been defaced with religious symbols using whitener pens and political messages with chalk. Some couples have carved their names on the rocks, permanently disfiguring them, the daily said.

“The site remained undisturbed till very recently, when a spurt in the number of tourists has led to many people organising illegal treks to the rock art site,” R Ranganathan, a man from Karikiyoor, said. Ranganathan and others plan to set up a group to regulate visitor entry into the forest reserve where the paintings are located.

C Maheswaran, former director of the Tribal Research Centre in Udhagamandalam, said the paintings were as old as the Indus Valley Civilization. “The rock paintings in Karikiyoor contain analogous-Indus script, meaning they resemble the script found in Indus civilization sites of northern India,” he said.

Maheswaran said the sites need to be preserved. He put the onus on the state archaeological department, the Archaeological Survey of India and the forest department to do so.

M Bathran, a village elder in Karikiyoor, said the Irula tribe has a deep cultural connection to the rock paintings, believing that their ancestors painted the symbols on the rocks. “Till today, we rely on these drawings to teach us the customs we should follow, remind us of our ties to the land, and the need to protect the forest,” he said.

Bathran alleged that the government did not seem to be interested in protecting the heritage. Therefore, the villagers had decided to put up warning boards prohibiting tourists from entering without permission. He said tourists will be allowed only under exceptional circumstances, and with guides.