The activists belonging to the Dravidar Viduthalai Kazhagam damaged the gate lights also, police said.
They had set ablaze the log wrapped in a gunny bag dipped in petrol before throwing it inside the premises at 5 AM.
Some pamphlets were also thrown inside the premises asking the Centre to respect the feelings and sentiments of Tamilians and Prime Minister Manmohan Singh and Khurshid not to attend the Commonwealth Heads of Government Meeting.
Some political parties in Tamil Nadu have been demanding that India boycott the CHOGM to be held in Sri Lanka next month on the Sri Lankan Tamils issue.