The crackers caught fire and exploded due to friction yesterday.
Sathyavani (40) and Pachchaiyammal (60), who were injured seriously, were rushed to the Sivakasi government hospital, where the former succumbed to her injuries yesterday.
Pachchiyammal died today, police said.
The owner of the unit Karuppiah had been arrested under various sections of IPC and Indian Explosive Act. Another owner of the factory Radhakrishnan was absconding, police said.