CHENNAI: This weekend, the lake at Mudichur in Tambaram, which usually wears a deserted look, saw an unusual clean-up crew at work. Along with students in T-shirts and caps scouring the water like treasure hunters, were 42 Marines from the guided-missile cruiser USS Bunker that is currently docked at Chennai for a joint Indo-US military exercise.

Armed with cleaning implements, the marines and students — over 60 of them from various schools and colleges across the city – fished out polythene, rubber, thermocol and other environmentally harmful materials from the highly polluted lake.