Rajan was "roughed up" by the public who caught him and he was found with 'external injuries' while being handed over to police, he said.
Mr. Rajendiran said he had "developed some problems," and was declared "brought dead" at a private hospital. However, post-mortem and RDO probe would confirm the cause of death, Mr. Rajendiran said.
Rajan demanded money at gunpoint after gaining entry into Elangovan's farm-house near here on Monday and went from room to room searching for cash. However, disappointed with what he got, Rajan subsequently opened fire using a country-made pistol, first killing Ramani and then Elangovan, injuring their daughter-in-law Vasanthi in the process, he said.
A sum of Rs 2.5 lakh and gold ornaments weighing seven sovereigns were recovered from him. He inflicted injuries on one of Elangovan's grandchildren but was overpowered by the car driver and others after Vasanthi raised an alarm, Mr. Rajendiran said. The case appeared to be a 'murder for gain'. "We are also looking if he had any accomplices," he said.