More than a decade after smoking was banned in public places, the menace still continues underground - in our crowded and poorly ventilated subways, no less. At the Churchgate railway station subway, one of the busiest in the city, there's even a shop illegally selling cigarettes, where customers openly light up, using the lighter generously provided by the shopkeeper.

Lighting up cigarettes in such a cramped, already airless public space is not only a health hazard for the 10 lakh pedestrians passing through the Churchgate subway, but is also a major fire risk. In fact, officials say cigarette butts, when not disposed properly, are among the top five causes of fire. Just one cigarette butt that's not been put out properly can spark a blaze that will only be fuelled further by combustible materials in the shops.