India, March 30 -- Neighbourhoods across south, east and southeast Delhi were pelted with a brief but deafening blast of devotional songs on Saturday night as Navratri processions, armed with giant boom boxes installed on trucks and carts, waltzed past on the eve of the nine-day festival.

Saturday's experience is likely to be only a harbinger of what lies ahead - over the years, these processions - which are also accompanied by blinding disco lights - have tormented residents along their routes, leaving them with many a sleepless night.

The Central Pollution Control Board allows a maximum noise level of 55dB(A) in residential areas between 6am and 10pm, which drops to 45dB(A) at night. For loudspeakers, noise at the boundary of a public...