The first floor of the house in the thickly populated colony came crashing down within seconds of the blast that occurred around 8.30 a.m.

An explosion at a house, where crackers were stocked up illegally, killed two persons of a family and critically injured another at Muneeswaran Colony here on Thursday.

The deceased were R. Muniyammal, 74, and her grandson M. Saravana Kumar, 22. Muniyammal’s daughter-in-law M. Sankareswari, 42, suffered a serious head injury and was referred to the Government Rajaji Hospital in Madurai.

The first floor of the house in the thickly populated colony came crashing down within seconds of the blast that occurred around 8.30 a.m. The explosion also heavily damaged the first-floor dwelling unit of the adjacent house that shared a common wall. The debris broke the balcony of the house across the narrow street. Three buildings adjacent to the house on the other side were also damaged.

Superintendent of Police S. Maheswaran said house owner R. Murugan, 45, had stealthily kept crackers brought from a fireworks unit at Sattur, with which he had a contract. “Aware of a raid on the unit, he transported excess crackers to his house only on Wednesday night to avoid penal action against the unit,” he said.

An elderly woman in the neighbourhood said Sankareswari, who had undergone surgery on the skull for cancer, was battling her ill-health to educate her three sons. “Despite the fall in eyesight, she was involved in tailoring work to take care of her children,” the woman said.

Though the first alert to a fire station claimed that there was an explosion of a cooking gas cylinder, six domestic cylinders found on the ground and first floors were intact, Divisional Fire Officer C. Manoharan said.

Murugan is absconding, the police said.

Police and Fire and Rescue Services personnel struggled till 3.30 p.m. to recover both bodies stuck under the debris. The bodies were taken to the government hospital here.