India, April 22 -- Scenes from a powerful explosion at a fireworks unit in Mundathicode were heartbreaking, as rescuers-mostly residents-described how the blast tore through a quiet paddy field, killing at least 13 people, injuring several others, and leaving widespread destruction.

Columns of thick black smoke rose high into the sky from a cluster of temporary sheds erected in the middle of the field, where firecrackers were being prepared for a local annual festival known for its spectacular fireworks and percussion ensembles.

A routine workday quickly descended into chaos at around 3.30 pm.

Firefighters and rescue personnel who rushed to the isolated site were forced to stop midway as intermittent explosions continued, sending shock...