NEW DELHI, March 13 (Xinhua) -- Indian police have arrested a 30-year-old tour guide in connection with the forest fire in the southern state of Tamil Nadu that killed 10 trekkers.

The massive fire broke out late Sunday evening when a group of nearly 40 people, mostly college students, went trekking in Kurangini hills in Theni district, some 540 km from state capital Chennai.

"The tour guide, who led the trekking group to the forest, has been arrested. He is being interrogated to ascertain his role," a police official said Tuesday.

While 10 people -- seven women and three men -- died in the fire, 30 others were rescued by Indian Air Force. "However, the death toll may go up as a few of the injured are said to be in critical condition in a government hospital," he added.

A probe has been ordered to ascertain the cause of the fire, the official said.