Stubble burning alone could not have led to this alarming spike in Delhi's air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital's skyline, a latest report on Delhi's toxic air quality has pointed out. Anumita Roychowdhury, executive director of Centre for Science and Environment, told NDTV that their latest report has found that PM2.5 levels in Delhi-NCR rose by a "staggering and unprecedented" 68 per cent within just 24 hours on November 2.