Bellandur Lake fire: Bengaluru's largest water body, the Bellandur Lake earlier in the week witnessed a huge fire which resulted in anxious moments for residents living nearby. The fire in the highly polluted Bellandur lake started in the middle of the wetlands and was witnessed by the locals when huge clouds of smoke were seen. According to an Indian Express report, the fire that raged for over seven hours is suspected to have started after miscreants set dry grass on the lakeshore ablaze, according to police and the state Pollution Control Board. But experts have a different take. According to A N Yellappa Reddy, an environmentalist, the deadly chemicals and large amounts of methane in the lake may have resulted in an accidental fire spreading over a vast area. This is not the first time when this polluted lake in the city has caught fire. The Bellandur Lake in the past witnessed occasional fires on its surface and scientists are blaming the pollutants in the water. According to an IISc study, "Discharge of untreated effluents (rich in hydrocarbons) with accidental fire (like throwing cigarettes, beedi) has led to the fire in the lake." It added that the "Incidence of foam catching fire are due to compounds with high flammability, i.e., mostly higher hydrocarbons and organic polymers from nearby industries\u2026High wind coupled with high intensity of rainfall leads to upwelling of sediments with the churning of water as it travels from higher elevation to lower elevation forming froth due to phosphorous," as per the report. WATCH| After the Bellandur Lake caught fire on January 19, pictures and videos of the smoke and fire soon went viral. The fire was doused by government agencies and Defence personnel. The viral videos and pictures raised concerns about apathy of civic agencies towards a recurring problem in the According to Defence officials, a strong contingent of 5,000 army jawans of the ASC centre led by Major General N S Rajpurohit doused the fire in the lake, according to PTI. Bengaluru Mayor R Sampath Raj said the fire seems to be an outcome of the accumulation of chemicals. The water samples will be collected and tested to find the reason behind the fire, he said. In the past the Bellandur lake had caught fire in May 2015 and August 2016. In 2015, the lake had turned into a frothy, foam-filled water body due to the high concentration of pollutants in the water. Foam from the lake had spilled onto the roads and other areas surrounding the lake. The Varthur lake also had caught fire in May, 2017 when some garbage was set ablaze.