As the air quality in Delhi continued to deteriorate, with pollution levels reaching hazardous levels, the Bharatiya Janata Party (BJP) today distributed protective masks across metro stations in the national capital. A thick layer of smog - a toxic blend of smoke and fog - enveloped the Delhi-National Capital Region this morning as the air quality index (AQI) plummeted to the "severe-plus" category, forcing authorities to announce stricter pollution control measures.