Police said Panneerselvam (45) and his nine-year-old daughter have been admitted to a private hospital while the other succumbed to injuries.
Pannerselvam's wife and mother-in-law found the three in a pool of blood at their home at Nedungundi near Pudupatti in the district and rushed them to hospital.
It was not known whether the injuries were inflicted by somebody else or Panneerselvam did it, police said, adding, investigation is on.