The Tamil Nadu Police on Monday arrested a man believed to be a tour guide who led the trekking group that got trapped in a forest fire in Theni district on Sunday, PTI reported. Ten trekkers were killed in the fire.

The police are questioning the man, Ranjith, to find out if he is linked to a Chennai-based travel group that is believed to have organised the expedition. The police are investigating how the trekking group came in touch with him.

The trekking team had 36 people, including three children. Tamil Nadu Chief Minister Edappadi Palaniswami said on Monday that the trekkers had not taken the required permission to be in the area. The local forest chief had also called it an “illegal trekking expedition”.