A senior police officer has told NDTV, that 30 students from Chennai had gone for trekking but "they did not take permission from police or the forest department." Local tribal people and forest personnel have reached the students, say police.

Students caught in Tamil Nadu forest fire being rescued
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"Southern Command is in touch with the Collector of Theni," tweeted the Defence Minister and 10-15 students have been rescued. They are already on their way down, Ms Sitharaman said.
A MI-17 chopper of the IAF is already on its way from Sulur to assess the situation as per sources in the defence ministry. An aerial survey will first be done to gauge the extent of damage.