BHOPAL, Nov. 1 -- Four workers died after entering a chamber at a hotel's basement for leftover food and residual waste at a hotel in western Madhya Pradesh's Ujjain district on Saturday night, a senior police officer said.

Ujjain Superintendent of Police (SP) Pradeep Sharma said the incident took place at Shri Ganga Hotel on Dewas Road in the district.

"Staff members along with some private individuals brought in for the task entered an above-ground chamber used for collecting leftover food and residual waste," Sharma said, adding that the workers collapsed due to toxic gas and a slippery surface.

A fifth cleaner, Hemraj, entered the chamber to help the four but managed to come out after experiencing breathing difficulties and dizzine...