The BJP's district unit president was arrested Tuesday for allegedly attacking the doctor of a primary health centre at Muthupettai here, police said.
They said eight people, who were given anti-Malaria tablets on December 29, allegedly developed complications and they had fainted.
They were later admitted to the PHC.
BJP district unit president Pettai Shiva had gone to the health centre to enquire about the treatment given to the affected people when an altercation took place between him and doctor Aravind, police said.
His supporters allegedly assaulted Aravind, they said.
On a complaint from the doctor, two of his supporters were arrested Monday.