LUCKNOW, Oct. 29 -- Nearly 32 hours after a tanker carrying formalin overturned on Kisan Path in Lucknow, the chemical was neutralised around 3am on Wednesday following a challenging, round-the-clock operation involving police, local residents, the National Disaster Response Force (NDRF) and the State Disaster Response Force (SDRF), officials said.

The operation proved difficult as the chemical's effects resurfaced whenever the sand spread over the spill was disturbed, causing irritation among personnel engaged in the containment efforts, DCP North Amit K Anand said adding face mask covering entire face was used.

"The Uttar Pradesh Pollution Control Board (UPPCB) was contacted for scientific assistance, following which its expertise was...