Kochi: Two sibling promoters of firecracker unit at Varappuzha have been booked over Tuesday evening's explosion which killed their brother and injured half a dozen people.

Brothers Jenson and Janson, who ran the ill-fated firecracker unit, have been named as accused in the case. They have been charged under the Indian Penal Code section on unintentional murder, reported Manorama News.

Their brother Davis had lost his life in the blast and six others, including children, were injured.

Jenson is reportedly missing ever since the incident.

Ernakulam District Collector Dr Renu Raj said on Tuesday that the unit did not have the licence to manufacture and store explosives.

The collector could not confirm if the unit had a display licence to sell the products locally.

The firecracker unit functioned in a densely populated locality at Muttinakam locality.

Even as the cause of the explosion is yet to be ascertained, authorities have not ruled out the possibility of the soaring temperature triggering a flare-up.

The district collector has sought a report from the Tahsildar and the Secretary of the Varapuzha Gram Panchayat.

Locals said they sensed an earthquake as the blast occurred.

Damages were reported from at least 15 houses in the vicinity and the impact was felt more than a kilometre away.