The students, who are from Erode and Coimbatore, were trekking to the Kurangani hills, when they got caught in the fire. The air force has been pressed into service for rescue operations, which has already been started by locals and forest personnel, who have reached the site, say police.
A MI-17 chopper of the Indian Air Force is already on its way from Sulur, to assess the situation say sources in the defence ministry. An aerial survey will first be done to gauge the extent of damage.
On a request from Chief Minister Palanisami, Defence Minister Nirmala Sitharaman instructed the Indian Air Force to help in rescue and evacuation of students.

Students caught in Tamil Nadu forest fire being rescued
A senior police officer has told NDTV, that 27 students from Chennai had gone for trekking but "they did not take permission from police or the forest department."
Ambulances and fire engines have been sent to the spot, fire officials told NDTV. The officials say since the area does not have good cell phone connectivity, detailed information is not available.
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"One of the members of the trekking team called 108 ambulance service and alerted about their situation", an official said.
Deputy Chief Minister of Tamil Nadu is on his way to the spot.