15 people of the trekkers were rescued.
Rescue operations are taken up by the fire and forest department officials. The Indian Airforce sent its two helicopters on the directives of Defence Minister Nirmala Sitharaman after she was approached for help by Chief Minister K Palaniswami.
State Health Minister C Vijayabaskar, in a tweet, said 15 of those trapped in the Kurangani hills had been rescued and were being treated for injuries at the government hospital in Bodinayakanur in the district in southern Tamil Nadu.
While initial reports said those trapped were students, officials later said the victims, belonging to two groups, were young women and men and three children who were on a mountain climbing/trekking training.
Stating that the cause of the fire was not known, he said efforts would be taken to strengthen the forest area security further.
Kurangani-Kozhukumalai hills are located near Bodinayakanur.