Four persons died and seven were injured in Morena district of Madhya Pradesh on Thursday after a house, where firecrackers were stored, collapsed after an explosion, reported India Today. Two nearby houses were also damaged.

The accident took place on Jaitpur Road in Banmore town. Several persons are also feared to be trapped under the debris. At least one child who was trapped has been rescued, Morena District Magistrate Bakki Karthikeyan told ANI.

He also said that the cause of the explosion could not be ascertained yet.

“We are investigating whether the blast was due to the gunpowder or due to a gas cylinder explosion,” added Karthikeyan, according to NDTV. “All the injured are critical, they have severe burn injuries.”

Among those who died, three persons were members of the same family. They have been identified as Anno Khan, her daughter Zoya and her son Mehmood, according to PTI.

An unidentified official said that Khan’s husband, Jameel, had stored firecrackers in the house without permission. He survived as he jumped off the terrace immediately after the blast, the official added.

Meanwhile, Congress leader and former Madhya Pradesh chief minister Kamal Nath demanded an inquiry into the incident. Nath also urged the government to take necessary precautions to prevent such incidents in view of the Diwali festival.