New Delhi/IBNS: Dense fog covered Delhi and Mumbai on Sunday morning as the air quality worsened in these metropolises. 

The air quality index (AQI) stood at 335 in Delhi at 8 am, which is categorised as "very poor", according to Central Pollution Control Board (CPCB) data.

People have been advised to avoid outdoor activities in the early morning and after sunset.

Several areas in the national capital recorded AQI above 350 - including Bawana 383, Mundka at 358, New Moti Bagh at 394, RK Puram at 368 and Wazirpur at 366, NDTV reported quoting SAFAR.

The Kartavya Path in Delhi as well as the high-rise buildings in Kalindi Kunj and nearby areas were hardly visible as they were covered in smog.

Authorities are sprinkling water using anti-smog guns to bring down the pollution levels, said reports.

The air quality in Mumbai was recorded in the "moderate" category (AQI 139) on Sunday morning.

Nanadeep Garden recorded the most polluted air at AQI 306, followed by Kandivali West with an AQI of 222. Bhandup, Colaba, Chembur, Bandra Kurla Complex, and Byculla are among the areas that recorded air quality in the moderate category, NDTV reported