The family had visited their native village, Thanthondrimalai in Karur district, and had started the return journey from their native village early on Wednesday morning.
They were on their way to Chennai when the mishap happened.
Police said Loganathan’s son Sivaraman (28) was driving car, while another son, Nirmal Kumar (26), daughter-in-law S Shalini (26), and grandson Rakshan (2) were on board at the time of the accident.
As they were near Veppur village in Cuddalore district on Wednesday, the car on which they were travelling collided with a TNSTC bus that was plying to Kallakurichi from Veppur. In the impact, Sivaraman and Nirmal Kumar were killed on the spot, while Shalini suffered grievous injuries.
But the two-year-old grandson had a miraculous escape, not sustaining any injury in the mishap.
Initial report suggested that the bus unexpectedly veered to the right side of the road, which led to the accident. Chief Minister Edappadi K Palaniswami expressed anguish and grief over the death Loganathan, Sivaraman and Nirmal Kumar in the accident.