Mathura, Oct. 6 -- Four students died, and another was injured after they were exposed to suspected toxic gas while cleaning an underground water tank (submersible tank) at a Sanskrit school (Gurukulam) in Vrindavan's Chaitanya Vihar, officials said.

District Magistrate Chandra Prakash Singh said the incident took place when students tried to clean an underground water tank after a foul smell was detected from it. The tank was around 12 to 14 feet deep.

"The gurukulam is being run by Ashish Kumar Sharma of Madhya Pradesh and has around 200 students enrolled, with nearly 100 currently residing on the premises. The students first removed water from the tank using a motor. After some water remained, they started cleaning it. One student we...