Ernakulam District Collector, Dr Renu Raj, has said the ill-fated firecracker unit at Varapuzha did not have the license to manufacture and store explosives.
The collector could not confirm if the unit had a display license to sell the products locally.
The firecracker unit functioned in a densely populated locality at Muttinakam. At the time of writing, an explosion at the unit killed one and seriously injured four others.
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 grama panchayat.
Locals said the explosion had felt like an earthquake. Damages were reported from at least 15 houses in the vicinity and the impact was felt more than a kilometre away.