Union Environment Minister Prakash Javadekar flagged off 50 CPCB inspection teams for field visits in Delhi-NCR on Thursday. The CPCB teams will keep a watch on pollution hot spots during the winter season. The Union Minister also urged Punjab govt to curb stubble burning. However, Javadekar added that stubble burning is not a major factor for air pollution. Delhi Chief Minister Arvind Kejriwal slammed Javadekar after he said that pollution in Delhi is due to local factors. Taking to Twitter, the Delhi CM sought to know as to why pollution suddenly increased. On Thursday, a layer of smoky haze lingered over the national capital. The air quality in the region took a hit as it reached 'very poor' levels. The 50 CPCB teams will make extensive field visits from October 15 to February 28 next year. The CPCB teams will focus on hot spots where air pollution is aggravated. Along with Delhi-NCR, teams will also visit places in UP, Haryana and Rajasthan.