Bulandshahr, Sep 23 (ANI): A gas cylinder on a moving bus exploded in Bulandshahr district of Uttar Pradesh, leaving four dead, including a woman and three children and injuring more than 70. Soon after the cylinder exploded, the bus caught fire. The four dead were rushed to the government hospitals in New Delhi. District Magistrate Nidhi Kesarwani said that the critically injured are being referred to burnt unit of Safdarjung hospital in New Delhi. Fifty five passengers received serious burn injuries and are being treated in Delhi hospitals. The condition of 15 other passengers is said to be critical. Many passengers were sitting on the roof top of the bus when the incident took place.