Prohibitory orders have been clamped in a seven km radius around the controversial Kundankulam Nuclear Power Plant (KNPP) as anti-nuclear activists have threaten to picket it on Monday.
Orders under Section 144 of the Indian Penal Code (IPC) come ahead of the protests planned by activists on the second anniversary of the Fukushima tragedy.
Officials said a total of 4,000 policemen had been deployed around the plant and a close vigil would be kept on movement of persons.
District collector, Mr Samayamurthy said he had banned assembly of more than four persons within this area.
People's Movement Against Nuclear Energy has threatened to picket the plant on Monday.
The Indo-Russian project was scheduled for commissioning in December 2011 but has been delayed following protests by locals citing safety concerns.
The 1000 MW first unit of the project is expected to be commissioned soon.