Four persons, including women and children, were injured after several vehicles collided on the Eastern Peripheral Expressway in the Delhi-National Capital Region on Friday, reported PTI.

Officials said that vehicles piled up on the highway in Greater Noida because of reduced visibility due to smog.

Residents in Delhi on Friday morning woke up under a blanket of smog after people defied the ban on bursting firecrackers on Diwali. The city’s overall air quality on Friday morning was 617 (hazardous), according to the System of Air Quality and Weather Forecasting And Research or SAFAR. The government-run monitoring agency reports real-time figures.

Air pollution in Delhi typically worsens in October and November due to farmers burning stubble in neighbouring states, unfavourable wind speed and emission of fumes by vehicles in the city. Firecrackers ignited for Diwali add to the problem.

Accidents due to pollution and smog occur regularly in Delhi-National Capital Region around this time of the year.

On Friday, a police spokesperson said that at first, a Hyundai i20 car rammed into a truck on the highway near Delhi. “Soon, some more vehicles that followed them came in speeding and piled up on the expressway,’’ the spokesperson added.

The police said that two trucks, one Swift and an Innova car were also involved in the accident, reported NDTV. Cranes had to be used to separate the mangled cars, according to the news channel.

The official said that all the injured persons – an official of the Haryana Cyber Cell, his wife and their two children – were in the car on the way to Palwal city. “While the husband and wife suffered serious injuries, the children had minor injuries,’’ the spokesperson added.

The official said that the husband and wife have been admitted to a hospital in Faridabad.

The police said they had made announcements to warn other drivers about low visibility on the road.