Delhi's Anand Vihar area recorded a PM10 level of 929 and PM2.5 level of 301 this morning.

Highlights Delhi air quality plummets to "severe" level, heat worsens problem

Pollution likely to last for next few days, people asked to stay indoors

Construction activity banned, fire brigade asked to sprinkle water

Residents have been there would be discomfort or breathing difficulties due to the pollution.

As a thick blanket of haze and dust enveloped Delhi and parts of the National Capital Region (NCR), the air quality nosedived to the "severe" level. The pollution masks are back and people have been advised to stay at home as the dusty conditions are likely to continue for the next few days. The PM10 level, presence of particles with diameter less than 10mm, was beyond severe at 796 in Delhi-NCR and 830 in Delhi particularly, leading to hazy conditions.An air quality index (AQI) between 0-50 is considered "Good", 51-100 "Satisfactory", 101-200 "Moderate", 201-300 "Poor", 301-400 "Very Poor", and 401-500 "Severe".For Delhi, which is reeling under scorching heat, it's a double whammy as the dust in the air isn't allowing the heat to escape. Among several measures taken to improve the air quality , all construction activities have been stopped, fire officials will sprinkle water and machines will sweep streets."There will be strong dust raising winds throughout the day. This will continue on Friday as well," an India Meteorological Department (IMD) official said.The breathlessness and the familiar burning of eyes and irritation in the throat have returned, and so were the attacks on Delhi Chief Minister Arvind Kejriwal and co. , who have been on a sit-in protest at Lieutenant Governor (LG) Anil Baijal's home for the last four days."Delhi is facing severe #pollution and dust particles are 18 times higher across the city and State and Central Govt representatives are sitting on "Dharna" in AC room. Where should the common man go?" asked a Twitter user.The toxic levels have prompted Mr Kejriwal to write to Prime Minister Narendra Modi, asking for urgent intervention to stop the "strike" by IAS officers, so the issue could be addressed. He added that no meeting on pollution control could be held over the last three months due to their ongoing "strike".According to MeT department, the wind speed of 25-35 kilometres per hour has been predicted for the day. The humidity level was 49 per cent this morning and the maximum temperature is expected to be around 41 degrees Celsius.According to the CPCB, the AQI -- a measurement of the concentration of toxic particulate matter in the air -- at several places in Delhi remained beyond the 500-mark, with east Delhi's Anand Vihar area recording a PM10 level of 929 and PM2.5 level of 301 this morning.The air quality in Delhi deteriorated beyond the "severe" level because of a ground-level dust storm in western India which increased coarser particles in the air, the Central Pollution Control Board data showed.Experts suggest that the pollution in Delhi has been worse than the smog episode in November last year. The CPCB, however, said the pollution of this season was different from November last year when both PM2.5 and PM10 had spiked. The current increase in levels of pollution is mainly due to drastic increase in coarse particles in air which has caused a spike in PM10 level, it said.A Sudhakar, CPCB member-secretary, has warned residents that the pollution level is expected remain like this for at least three to four days and there could be discomfort or breathing difficulties due to the pollution.A report by the World Health Organisation last month said India was home to the world's 14 most polluted cities, with Delhi ranked sixth most polluted.Dust storm has also affected other north Indian cities as well. Flight operations have been suspended at the Chandigarh Airport due to poor visibility following dust storm.

While an Air India flight between Mumbai and Chandigarh was stranded at Delhi airport due to a sandstorm in Chandigarh, budget airline SpiceJet said all departures/arrivals and their consequential flights might get affected.Vistara and Jet Airways also informed passengers about delays due to bad weather.