The 37-year old woman, identified as Vinotha of Chennai, was travelling to Chennai along with her relative in the car.
When they reached near Sirkazhi in the highway, an SUV had hit the car from behind. When the driver stopped the car, a 10-member gang from the SUV broken the windshield of the car and hacked Vinotha to death, police said, adding, previous enmity was suspected to be the reason behind the murder.
Police said Vinotha's husband Radhakrishnan was also hacked to death at TR Pattinam In January, 2013.