Despite the lockdown, many residents brought Vinayaka idols from their houses and immersed them in the Mookaneri, Kumaragiri and Veeranam lakes here on Monday.
According to police, the immersion of the idols were carried out in Salem rural areas and in Namakkal on Saturday itself.
Officials from the Tamil Nadu Pollution Control Board said that they may collect samples later to check water quality and assess level of pollution, if any.
Immersion of Vinayaka idols were also held in Krishnagiri district. Two teenagers, who went to immerse the idols in Thoorai lake near Shoolagiri, drowned on Monday after they went to the deeper part of the waterbody. The deceased were identified as Bhagavathi (13) and Murali (13). Shoolagiri police are investigating.