Two men were charred to death and another was injured when the ambulance they were sleeping in caught fire in south Delhi's Sheikh Sarai area in the early hours today, said an officer from the Delhi Fire Service. A call was received at 12.50 am about the blaze, and two fire tenders were rushed to the spot. The deceased were identified as Guddu (25) and Rahul (24), he said. The injured man was identified as 40-year-old Subodh. He suffered 40 per cent burn injuries and was admitted to the Safdarjung Hospital. The ambulance driver would burn egg trays to keep mosquitoes at bay. It is suspected that the fire started from the trays. The storm last night caused it spread to other ambulances parked nearby, the police said. Guddu and Rahul were found dead inside the ambulance. Subodh was rushed to hospital, where he was critical, the police said. The three persons were employees of the Rana Ambulance Service in Khanpur. Deputy Commissioner of Police (South) Romil Baaniya said a case had been registered against unidentified persons in connection with the incident. A forensics team was called in to ascertain the cause of the fire. The bodies were handed over to their families after post-mortem, the police said. Rahul had been working with the ambulance service for the last one and a half years, while Guddu had joined it 15 days ago. Subodh had also been working for a long time. Rahul's brother Shubham said it was surprising that Rahul did not retire to his rented accomodation and slept in the ambulance instead. "Rahul rented a room in Neb Sarai. He would go and sleep there. But yesterday, he was asked to sleep in the ambulance. It is very strange. We want this aspect to be investigated," he said.