A day after nearly 35 students fell unconscious at M S University's (MSU) C C Mehta Auditorium, the Forensic Science Laboratory (FSL) has submitted its preliminary report prepared in consultation with the maintenance contractor of the auditorium's airconditioning units.

The FSL's preliminary report has revealed that the incident occurred due to suffocation.

Vam Services, a city-based company, had the maintenance contract of the auditorium's ACs for the last several months.

R C Gondalia, an FSL expert, said, "The incident occurred primarily because of suffocation."

Gondalia, who inspected the place at night, said, "The lighting up of 108 diyas (lamps) during the event could have generated higher levels of carbon monoxide causing nausea and giddiness among students."

He further said, "Another cause of the incident could have been choking of the AC ducts, which facilitate air circulation."

Vinod Patel, the auditorium in-charge, said, "The performers had requested us to switch off the ACs for around 10 minutes so that the lamps didn't flicker."

The university authorities, meanwhile, ruled out the possibility of gas leakage saying that the air conditioning plant in the auditorium did not use feron gas used in conventional plants.