evidence: As several parts of north India woke up to dense fog, several people were injured and 12 vehicles crashed in a massive pile-up on a Yamuna Expressway stretch near Greater Noida. The pile-up took place at Jewar on the Noida-Agra route. Visuals from the site showed damaged vehicles, including trucks and cars, at the pile-up site. In the videos could be seen several boards used on construction sites to demarcate roadside pits. It appears that the vehicles driving through the dense fog failed to spot the boards and crashed into them, leading to the pile-up. The Jewar pile-up was one among many such incidents that took place this morning when the Delhi and neighbouring cities had near zero visibility. In a similar pile-up of six vehicles on Agra-Lucknow expressway, one person was killed and six others were injured.