Four labourers sleeping in the basement of a hotel here were found dead on Saturday, police said.The labourers had lit a coal bonfire before sleeping, the police said which might have led to carbon monoxide poisoning as they asphyxiated due to the fumes from the fire lit to keep out the extreme cold prevailing in the city.The incident took place in a hotel in Vibhuti Khand of the posh Gomtinagar area. The hotel staff said that after working on a civil project in the hotel, the four had retired to the accommodation offered to them by the management in the basement.Their bodies were discovered in the morning when they did not report for work and the contractor went looking for them in the basement. The victims were identified as Raj Kumar, Ram Naresh, Nihal Ahmad and Mohammad Shahid. The bodies have been sent for post-mortem and their families have been informed.