Gurgaon: About 40 passengers had a narrow escape on Saturday evening when the CNG fuelled Delhi Transport Corporation (DTC) bus in which they were travelling went up in flames near the Management Development Institute(MDI) in Gurgaon. Fire department officials said that initial investigations have shown that the CNG bus caught fire because of a leak in the gas cylinder. According to eyewitnesses, the bus, which plies on the Karol Bagh-Gurgaon route, caught fire around 6 pm, after it reached the MDI Chowk on Mehrauli Gurgaon road. No one was hurt as all the passengers had got down from the bus before the mishap took place.