Mumbai, May 7 -- The Forensic Science Laboratory (FSL) has detected zinc phosphide, a chemical commonly used in rat poison, in the bodies of four members of a family from Mumbai's Pydhonie area as well as in watermelon samples recovered from their residence, shifting the investigation away from suspected food poisoning.

The forensic report was submitted to Mumbai Police 11 days after the deaths of the family members, who had allegedly consumed biryani and watermelon before they were found dead under mysterious circumstances last month.

According to FSL officials, zinc phosphide is a highly toxic substance commonly used for rodent control and as a single-dose poison in agricultural fields and grain storage facilities. Officials stated that...