Thiruvananthapuram | Four women sustained burn injuries in a blast at a firecrackers manufacturing unit in Palode near here on Tuesday, police said.

The incident occurred around 10 am and all the injured were rushed to the government medical college hospital here.

According to police, the explosion was caused by an accidental spark while making firecrackers.

"One woman sustained 50 per cent burns. The others suffered minor burns as per the preliminary information received," they said.

An investigation is on and more details are being collected, they added.